printf long changes variable when it's digits is more than 9 chars
I have this simple code in C, whenever I enter an id number that longer than 9 digits, it prints a different number. What's the wrong?
void main() {
long id1;
double l1, w1;
printf("enter studint 1 id,lenght and weight: n");
scanf("%ld %lf %lf", &id1, &l1, &w1);
printf("STUDINTS INFORMATION:");
printf("nn%-10.0ldt %-4.3lft %-4.3lfn", id1, l1, w1);
}
c printf scanf
edited Nov 25 '18 at 9:04
chqrlie
60.2k747102
asked Nov 25 '18 at 4:57
Majd SadiMajd Sadi
155
add a comment |
I have this simple code in C, whenever I enter an id number that longer than 9 digits, it prints a different number. What's the wrong?
void main() {
long id1;
double l1, w1;
printf("enter studint 1 id,lenght and weight: n");
scanf("%ld %lf %lf", &id1, &l1, &w1);
printf("STUDINTS INFORMATION:");
printf("nn%-10.0ldt %-4.3lft %-4.3lfn", id1, l1, w1);
}
c printf scanf
edited Nov 25 '18 at 9:04
chqrlie
60.2k747102
asked Nov 25 '18 at 4:57
Majd SadiMajd Sadi
155
start by checking the return value ofscanf().
– Sourav Ghosh
Nov 25 '18 at 4:58
1
"I enter an id number that longer than 9 digits" --> What was the number entered? What was printed?
– chux
Nov 25 '18 at 5:00
3
Alongrange may only be [-2,147,483,647 ... 2,147,483,647]. A number outside that range is asking for trouble. Use a wider integer type.
– chux
Nov 25 '18 at 5:03
%-10.0ldforid1seems incorrect: ifid1 == 0the output will be just 10 spaces.
– chqrlie
Nov 25 '18 at 9:10
add a comment |
I have this simple code in C, whenever I enter an id number that longer than 9 digits, it prints a different number. What's the wrong?
void main() {
long id1;
double l1, w1;
printf("enter studint 1 id,lenght and weight: n");
scanf("%ld %lf %lf", &id1, &l1, &w1);
printf("STUDINTS INFORMATION:");
printf("nn%-10.0ldt %-4.3lft %-4.3lfn", id1, l1, w1);
}
c printf scanf
edited Nov 25 '18 at 9:04
chqrlie
60.2k747102
asked Nov 25 '18 at 4:57
Majd SadiMajd Sadi
155
I have this simple code in C, whenever I enter an id number that longer than 9 digits, it prints a different number. What's the wrong?
void main() {
long id1;
double l1, w1;
printf("enter studint 1 id,lenght and weight: n");
scanf("%ld %lf %lf", &id1, &l1, &w1);
printf("STUDINTS INFORMATION:");
printf("nn%-10.0ldt %-4.3lft %-4.3lfn", id1, l1, w1);
}
c printf scanf
c printf scanf
edited Nov 25 '18 at 9:04
chqrlie
60.2k747102
asked Nov 25 '18 at 4:57
Majd SadiMajd Sadi
155
edited Nov 25 '18 at 9:04
chqrlie
60.2k747102
asked Nov 25 '18 at 4:57
Majd SadiMajd Sadi
155
edited Nov 25 '18 at 9:04
chqrlie
60.2k747102
edited Nov 25 '18 at 9:04
chqrlie
60.2k747102
edited Nov 25 '18 at 9:04
chqrlie
60.2k747102
60.2k747102
asked Nov 25 '18 at 4:57
Majd SadiMajd Sadi
155
asked Nov 25 '18 at 4:57
Majd SadiMajd Sadi
155
asked Nov 25 '18 at 4:57
Majd SadiMajd Sadi
155
155
start by checking the return value ofscanf().
– Sourav Ghosh
Nov 25 '18 at 4:58
1
"I enter an id number that longer than 9 digits" --> What was the number entered? What was printed?
– chux
Nov 25 '18 at 5:00
3
Alongrange may only be [-2,147,483,647 ... 2,147,483,647]. A number outside that range is asking for trouble. Use a wider integer type.
– chux
Nov 25 '18 at 5:03
%-10.0ldforid1seems incorrect: ifid1 == 0the output will be just 10 spaces.
– chqrlie
Nov 25 '18 at 9:10
add a comment |
start by checking the return value ofscanf().
– Sourav Ghosh
Nov 25 '18 at 4:58
1
"I enter an id number that longer than 9 digits" --> What was the number entered? What was printed?
– chux
Nov 25 '18 at 5:00
3
Alongrange may only be [-2,147,483,647 ... 2,147,483,647]. A number outside that range is asking for trouble. Use a wider integer type.
– chux
Nov 25 '18 at 5:03
%-10.0ldforid1seems incorrect: ifid1 == 0the output will be just 10 spaces.
– chqrlie
Nov 25 '18 at 9:10
start by checking the return value of
scanf().– Sourav Ghosh
Nov 25 '18 at 4:58
start by checking the return value of
scanf().– Sourav Ghosh
Nov 25 '18 at 4:58
1
1
"I enter an id number that longer than 9 digits" --> What was the number entered? What was printed?
– chux
Nov 25 '18 at 5:00
"I enter an id number that longer than 9 digits" --> What was the number entered? What was printed?
– chux
Nov 25 '18 at 5:00
3
3
A
long range may only be [-2,147,483,647 ... 2,147,483,647]. A number outside that range is asking for trouble. Use a wider integer type.– chux
Nov 25 '18 at 5:03
A
long range may only be [-2,147,483,647 ... 2,147,483,647]. A number outside that range is asking for trouble. Use a wider integer type.– chux
Nov 25 '18 at 5:03
%-10.0ld for id1 seems incorrect: if id1 == 0 the output will be just 10 spaces.– chqrlie
Nov 25 '18 at 9:10
%-10.0ld for id1 seems incorrect: if id1 == 0 the output will be just 10 spaces.– chqrlie
Nov 25 '18 at 9:10
add a comment |
3 Answers
3
active
oldest
votes
You use type long for id1 which may have range of just -2147483647 to 2147483647 depending on the target system architecture. This type cannot be used to store larger numbers on your system.
Incidentally, the format %-10.0ld for id1 seems incorrect as the output for the value 0 will be just 10 spaces. The precision field does not specify the number of decimals for integers, but the minimum number of digits.
Note also that main without arguments should have a prototype of int main(void), and you should test the return value of scanf() to avoid undefined behavior on invalid input.
To solve your problem, here are possible solutions:
You could use type
doublebut I would not advise so.You could try type
long long int, but this type may not be fully supported on your system.I suggest you use a character string for your purpose.
Here is a modified version:
#include <stdio.h>
int main(void) {
char id1[20];
double l1, w1;
printf("enter student 1 id, height and weight:n");
if (scanf("%19s%lf%lf", id1, &l1, &w1) != 3) {
printf("invalid inputn");
return 1;
}
printf("STUDENT INFORMATION:n");
printf("n%-10st %-4.3ft %-4.3fn", id1, l1, w1);
return 0;
}
answered Nov 25 '18 at 9:19
chqrliechqrlie
60.2k747102
add a comment |
Usually, IDs are better stored as strings. Not only is it more flexible if the ID someday contains letters, but it avoids problems like this. IDs are not arithmetic, i.e. you cannot typically get anything out of adding or subtracting them, so you may as well just store them as strings. Then you can easily support any length, regardless of the width of various integer types on your system.
answered Nov 25 '18 at 5:13
John ZwinckJohn Zwinck
153k17177294
add a comment |
That's because range of long in C is from -2,147,483,648 to 2,147,483,647.
So, when you try to save a number longer than 9 digits it gets out of range.
For more details on the range of variables in C: https://www.tutorialspoint.com/cprogramming/c_data_types.htm
answered Nov 25 '18 at 5:19
Mangaldeep PannuMangaldeep Pannu
8217
This tutorial is incorrect. The range of typelongis at least-2147483647to2147483647but it may be much larger, as is the case on 64-bit linux systems. Your correctly diagnosed the OP's problem, but the link is misleading.
– chqrlie
Nov 25 '18 at 9:10
add a comment |
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3 Answers
3
active
oldest
votes
3 Answers
3
active
oldest
votes
active
oldest
votes
active
oldest
votes
You use type long for id1 which may have range of just -2147483647 to 2147483647 depending on the target system architecture. This type cannot be used to store larger numbers on your system.
Incidentally, the format %-10.0ld for id1 seems incorrect as the output for the value 0 will be just 10 spaces. The precision field does not specify the number of decimals for integers, but the minimum number of digits.
Note also that main without arguments should have a prototype of int main(void), and you should test the return value of scanf() to avoid undefined behavior on invalid input.
To solve your problem, here are possible solutions:
You could use type
doublebut I would not advise so.You could try type
long long int, but this type may not be fully supported on your system.I suggest you use a character string for your purpose.
Here is a modified version:
#include <stdio.h>
int main(void) {
char id1[20];
double l1, w1;
printf("enter student 1 id, height and weight:n");
if (scanf("%19s%lf%lf", id1, &l1, &w1) != 3) {
printf("invalid inputn");
return 1;
}
printf("STUDENT INFORMATION:n");
printf("n%-10st %-4.3ft %-4.3fn", id1, l1, w1);
return 0;
}
answered Nov 25 '18 at 9:19
chqrliechqrlie
60.2k747102
add a comment |
You use type long for id1 which may have range of just -2147483647 to 2147483647 depending on the target system architecture. This type cannot be used to store larger numbers on your system.
Incidentally, the format %-10.0ld for id1 seems incorrect as the output for the value 0 will be just 10 spaces. The precision field does not specify the number of decimals for integers, but the minimum number of digits.
Note also that main without arguments should have a prototype of int main(void), and you should test the return value of scanf() to avoid undefined behavior on invalid input.
To solve your problem, here are possible solutions:
You could use type
doublebut I would not advise so.You could try type
long long int, but this type may not be fully supported on your system.I suggest you use a character string for your purpose.
Here is a modified version:
#include <stdio.h>
int main(void) {
char id1[20];
double l1, w1;
printf("enter student 1 id, height and weight:n");
if (scanf("%19s%lf%lf", id1, &l1, &w1) != 3) {
printf("invalid inputn");
return 1;
}
printf("STUDENT INFORMATION:n");
printf("n%-10st %-4.3ft %-4.3fn", id1, l1, w1);
return 0;
}
answered Nov 25 '18 at 9:19
chqrliechqrlie
60.2k747102
add a comment |
You use type long for id1 which may have range of just -2147483647 to 2147483647 depending on the target system architecture. This type cannot be used to store larger numbers on your system.
Incidentally, the format %-10.0ld for id1 seems incorrect as the output for the value 0 will be just 10 spaces. The precision field does not specify the number of decimals for integers, but the minimum number of digits.
Note also that main without arguments should have a prototype of int main(void), and you should test the return value of scanf() to avoid undefined behavior on invalid input.
To solve your problem, here are possible solutions:
You could use type
doublebut I would not advise so.You could try type
long long int, but this type may not be fully supported on your system.I suggest you use a character string for your purpose.
Here is a modified version:
#include <stdio.h>
int main(void) {
char id1[20];
double l1, w1;
printf("enter student 1 id, height and weight:n");
if (scanf("%19s%lf%lf", id1, &l1, &w1) != 3) {
printf("invalid inputn");
return 1;
}
printf("STUDENT INFORMATION:n");
printf("n%-10st %-4.3ft %-4.3fn", id1, l1, w1);
return 0;
}
answered Nov 25 '18 at 9:19
chqrliechqrlie
60.2k747102
You use type long for id1 which may have range of just -2147483647 to 2147483647 depending on the target system architecture. This type cannot be used to store larger numbers on your system.
Incidentally, the format %-10.0ld for id1 seems incorrect as the output for the value 0 will be just 10 spaces. The precision field does not specify the number of decimals for integers, but the minimum number of digits.
Note also that main without arguments should have a prototype of int main(void), and you should test the return value of scanf() to avoid undefined behavior on invalid input.
To solve your problem, here are possible solutions:
You could use type
doublebut I would not advise so.You could try type
long long int, but this type may not be fully supported on your system.I suggest you use a character string for your purpose.
Here is a modified version:
#include <stdio.h>
int main(void) {
char id1[20];
double l1, w1;
printf("enter student 1 id, height and weight:n");
if (scanf("%19s%lf%lf", id1, &l1, &w1) != 3) {
printf("invalid inputn");
return 1;
}
printf("STUDENT INFORMATION:n");
printf("n%-10st %-4.3ft %-4.3fn", id1, l1, w1);
return 0;
}
answered Nov 25 '18 at 9:19
chqrliechqrlie
60.2k747102
answered Nov 25 '18 at 9:19
chqrliechqrlie
60.2k747102
answered Nov 25 '18 at 9:19
chqrliechqrlie
60.2k747102
answered Nov 25 '18 at 9:19
chqrliechqrlie
60.2k747102
60.2k747102
add a comment |
add a comment |
Usually, IDs are better stored as strings. Not only is it more flexible if the ID someday contains letters, but it avoids problems like this. IDs are not arithmetic, i.e. you cannot typically get anything out of adding or subtracting them, so you may as well just store them as strings. Then you can easily support any length, regardless of the width of various integer types on your system.
answered Nov 25 '18 at 5:13
John ZwinckJohn Zwinck
153k17177294
add a comment |
Usually, IDs are better stored as strings. Not only is it more flexible if the ID someday contains letters, but it avoids problems like this. IDs are not arithmetic, i.e. you cannot typically get anything out of adding or subtracting them, so you may as well just store them as strings. Then you can easily support any length, regardless of the width of various integer types on your system.
answered Nov 25 '18 at 5:13
John ZwinckJohn Zwinck
153k17177294
add a comment |
Usually, IDs are better stored as strings. Not only is it more flexible if the ID someday contains letters, but it avoids problems like this. IDs are not arithmetic, i.e. you cannot typically get anything out of adding or subtracting them, so you may as well just store them as strings. Then you can easily support any length, regardless of the width of various integer types on your system.
answered Nov 25 '18 at 5:13
John ZwinckJohn Zwinck
153k17177294
Usually, IDs are better stored as strings. Not only is it more flexible if the ID someday contains letters, but it avoids problems like this. IDs are not arithmetic, i.e. you cannot typically get anything out of adding or subtracting them, so you may as well just store them as strings. Then you can easily support any length, regardless of the width of various integer types on your system.
answered Nov 25 '18 at 5:13
John ZwinckJohn Zwinck
153k17177294
answered Nov 25 '18 at 5:13
John ZwinckJohn Zwinck
153k17177294
answered Nov 25 '18 at 5:13
John ZwinckJohn Zwinck
153k17177294
answered Nov 25 '18 at 5:13
John ZwinckJohn Zwinck
153k17177294
153k17177294
add a comment |
add a comment |
That's because range of long in C is from -2,147,483,648 to 2,147,483,647.
So, when you try to save a number longer than 9 digits it gets out of range.
For more details on the range of variables in C: https://www.tutorialspoint.com/cprogramming/c_data_types.htm
answered Nov 25 '18 at 5:19
Mangaldeep PannuMangaldeep Pannu
8217
This tutorial is incorrect. The range of typelongis at least-2147483647to2147483647but it may be much larger, as is the case on 64-bit linux systems. Your correctly diagnosed the OP's problem, but the link is misleading.
– chqrlie
Nov 25 '18 at 9:10
add a comment |
That's because range of long in C is from -2,147,483,648 to 2,147,483,647.
So, when you try to save a number longer than 9 digits it gets out of range.
For more details on the range of variables in C: https://www.tutorialspoint.com/cprogramming/c_data_types.htm
answered Nov 25 '18 at 5:19
Mangaldeep PannuMangaldeep Pannu
8217
This tutorial is incorrect. The range of typelongis at least-2147483647to2147483647but it may be much larger, as is the case on 64-bit linux systems. Your correctly diagnosed the OP's problem, but the link is misleading.
– chqrlie
Nov 25 '18 at 9:10
add a comment |
That's because range of long in C is from -2,147,483,648 to 2,147,483,647.
So, when you try to save a number longer than 9 digits it gets out of range.
For more details on the range of variables in C: https://www.tutorialspoint.com/cprogramming/c_data_types.htm
answered Nov 25 '18 at 5:19
Mangaldeep PannuMangaldeep Pannu
8217
That's because range of long in C is from -2,147,483,648 to 2,147,483,647.
So, when you try to save a number longer than 9 digits it gets out of range.
For more details on the range of variables in C: https://www.tutorialspoint.com/cprogramming/c_data_types.htm
answered Nov 25 '18 at 5:19
Mangaldeep PannuMangaldeep Pannu
8217
answered Nov 25 '18 at 5:19
Mangaldeep PannuMangaldeep Pannu
8217
answered Nov 25 '18 at 5:19
Mangaldeep PannuMangaldeep Pannu
8217
answered Nov 25 '18 at 5:19
Mangaldeep PannuMangaldeep Pannu
8217
8217
This tutorial is incorrect. The range of typelongis at least-2147483647to2147483647but it may be much larger, as is the case on 64-bit linux systems. Your correctly diagnosed the OP's problem, but the link is misleading.
– chqrlie
Nov 25 '18 at 9:10
add a comment |
This tutorial is incorrect. The range of typelongis at least-2147483647to2147483647but it may be much larger, as is the case on 64-bit linux systems. Your correctly diagnosed the OP's problem, but the link is misleading.
– chqrlie
Nov 25 '18 at 9:10
This tutorial is incorrect. The range of type
long is at least -2147483647 to 2147483647 but it may be much larger, as is the case on 64-bit linux systems. Your correctly diagnosed the OP's problem, but the link is misleading.– chqrlie
Nov 25 '18 at 9:10
This tutorial is incorrect. The range of type
long is at least -2147483647 to 2147483647 but it may be much larger, as is the case on 64-bit linux systems. Your correctly diagnosed the OP's problem, but the link is misleading.– chqrlie
Nov 25 '18 at 9:10
add a comment |
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start by checking the return value of
scanf().– Sourav Ghosh
Nov 25 '18 at 4:58
1
"I enter an id number that longer than 9 digits" --> What was the number entered? What was printed?
– chux
Nov 25 '18 at 5:00
3
A
longrange may only be [-2,147,483,647 ... 2,147,483,647]. A number outside that range is asking for trouble. Use a wider integer type.– chux
Nov 25 '18 at 5:03
%-10.0ldforid1seems incorrect: ifid1 == 0the output will be just 10 spaces.– chqrlie
Nov 25 '18 at 9:10