C Programming Questions and Answers – Data Types and Sizes – 2
C Programming Questions and Answers – Data Types and Sizes – 2
1.Comment on the output of this C code?
#include <stdio.h>
int main()
{
float f1 = 0.1;
if (f1 == 0.1)
printf(“equal\n”);
else
printf(“not equal\n”);
}
a) equal
b) not equal
c) Output depends on compiler
d) None of the mentioned
View Answer
Answer:b
Explanation:0.1 by default is of type double which has different representation than float resulting in inequality even after conversion.
Output:
$ cc pgm4.c
$ a.out
not equal
2.Comment on the output of this C code?
#include <stdio.h>
int main()
{
float f1 = 0.1;
if (f1 == 0.1f)
printf(“equal\n”);
else
printf(“not equal\n”);
}
a) equal
b) not equal
c) Output depends on compiler
d) None of the mentioned
View Answer
Answer:a
Explanation:0.1f results in 0.1 to be stored in floating point representations.
Output:
$ cc pgm5.c
$ a.out
Equal
3.What is the output of this C code (on a 32-bit machine)?
#include <stdio.h>
int main()
{
int x = 10000;
double y = 56;
int *p = &x;
double *q = &y;
printf(“p and q are %d and %d”, sizeof(p), sizeof(q));
return 0;
}
a) p and q are 4 and 4
b) p and q are 4 and 8
c) Compiler error
d) p and q are 2 and 8
View Answer
Answer:a
Explanation:Size of any type of pointer is 4 on a 32-bit machine.
Output:
$ cc pgm6.c
$ a.out
p and q are 4 and 4
4.Which is correct with respect to size of the datatypes?
a) char > int > float
b) int > char > float
c) char < int < double
d) double > char > int
View Answer
Answer:c
Explanation:char has lesser bytes than int and int has lesser bytes than double in any system
5.What is the output of the following C code(on a 64 bit machine)?
#include <stdio.h>
union Sti
{
int nu;
char m;
};
int main()
{
union Sti s;
printf(“%d”, sizeof(s));
return 0;
}
a) 8
b) 5
c) 9
d) 4
View Answer
Answer:d
Explanation:Since the size of a union is the size of its maximum datatype, here int is the largest hence 4.
Output:
$ cc pgm7.c
$ a.out
4
6.What is the output of this C code?
#include <stdio.h>
int main()
{
float x = ‘a’;
printf(“%f”, x);
return 0;
}
a) a
b) run time error
c) a.0000000
d) 97.000000
View Answer
Answer:d
Explanation:Since the ASCII value of a is 97, the same is assigned to the float variable and printed.
Output:
$ cc pgm8.c
$ a.out
97.000000
7.Which of the datatypes have size that is variable?
a) int
b) struct
c) float
d) double
View Answer
Answer:b
Explanation:Since the size of the structure depends on its fields, it has a variable size.
Answer:c
Output:
$ cc pgm.c
$ a.out
$
