C-Programming |Gate-2017|
1. Consider the following C code:
#include <stdio.h>
int *assignval(int *x, int val) {
*x = val;
return x;
}
void main ( ) {
int *x = malloc(sizeof(int));
if(NULL == x) return;
x = assignval(x, 0);
if(x) {
x = (int *)malloc(size of(int));
if(NULL == x) return;
x = assignval(x, 10);
}
printf(“%dn”, *x);
free(x);
}
The code suffers from which one of the following problems: [GATE -2017]
a. compiler error as the return of malloc is not typecast approximately
b. compiler error because the comparison should be made as x==NULL and not as shown
c. compiles successfully but execution may result in dangling pointer
d. compiles successfully but execution may result in memory leak
Answer : d)
2. Consider the following two functions.
void fun1(int n) { void fun2(int n) {
if(n == 0) return; if(n == 0) return;
printf(“%d”, n); printf(“%d”, n);
fun2(n – 2); fun1(++n);
printf(“%d”, n); printf(“%d”, n);
}
}
The output printed when fun1(5) is called is : [GATE -2017]
a. 53423122233445
b. 53423120112233
c. 53423122132435
d. 53423120213243
Answer : a)
3. Consider the C functions foo and bar given below:
int foo(int val) {
int x = 0;
while (val>0) {
x = x + foo(val–);
}
return val;
}
int bar(int val) {
int x = 0;
while (val>0) {
x = x + bar(val-1);
}
return val;
}
Invocations of foo(3) and bar(3) will result in: [GATE -2017]
a. Return of 6 and 6 respectively.
b. Infinite loop and abnormal termination respectively
c. Abnormal termination and infinite loop respectively.
d. Both terminating abnormally.
Answer : c)
4. Consider the following C program.
#include <stdio.h>
#include <string.h>
void printlength (char*s, char*t) {
unsigned int c = 0;
int len = ((strlen(s) – strlen(t)) > c) ? strlen(s):strlen(t);
printf(“%d\n”, len);
}
void main () {
char*x = “abc”;
char*y = “defgh”;
printlength(x,y);
}
Recall that strlen is defined in string.h as returning a value of type size_t, which is an unsigned int. The output of the program is _________. [GATE -2017]
a. 3
b. 4
c. 5
d. 6
Answer : a)
5. The output of executing the following C program is __________. [GATE -2017]
#include<stdio.h>
int total (int v) {
static int count=0;
while(v) {
count += v&1;
v ≫= 1;
}
return count;
}
void main() {
static int x = 0;
int i = 5;
for(; 1> 0; i–) {
x = x + total(i);
}
printf(“%d\n”, x);
}
a. 23
b. 24
c. 25
d. 26
Answer : a)
6. Match the following: [GATE -2017]
a. P→(ii), Q→(iv), R→(i), S→(iii)
b. P→(ii), Q→(i), R→(iv), S→(iii)
c. P→(ii), Q→(iv), R→(iii), S→(i)
d. P→(iii), Q→(iv), R→(i), S→(ii)
Answer : a)
7. Consider the following function implemented in C:
void printxy (int x, int y) {
int *ptr;
x = 0;
ptr = &x;
y = *ptr;
*ptr = 1;
printf(“%d,%d”,x,y);
}
The output of invoking printxy(1, 1) is : [GATE -2017]
a. 0,0
b. 0,1
c. 1,0
d. 1,1
Answer : c)
8. Consider the C program fragment below which is meant to divide x and y using repeated subtractions. The variables x, y, q and r are all unsigned int.
while (r >= y) {
r = r – y;
q = q + 1;
}
Which of the following conditions on the variables x, y, q and r before the execution of the fragment will ensure that the loop terminates in a state satisfying the condition x == (y*q + r)? [GATE -2017]
a. (q == r) && (r == 0)
b. (x > 0) && (r == x) && (y > 0)
c. (q == 0) && (r == x) && (y > 0)
d. (q == 0) && (y > 0)
Answer : c)
C-Programming |Gate-2017|
9. Consider the following snippet of a C program. Assume that swap(&x, &y) exchanges the contents of x and y.
int main ()
{
int array[] = {3, 5, 1, 4, 6, 2};
int done = 0, i;
done = 1;
for (i=0; i<=4; i++) {
if (array[i] < array[i+1]) {
swap (&array[i], &array[i+1]);
done = 0;
}
}
for (i=5; i>=1; i–) {
if (array[i] > array[i-1]) {
swap(&array[i], &array[i-1]);
done=0;
}
}}
printf(“%d”, array[3]);
}
The output of the program is ___________. : [GATE -2017]
a. 3
b. 4
c. 5
d. 6
Answer : a)
C-Programming |Gate-2017|
10. Consider the following C program.
#include
int main ()
{
int m=10;
int n, n1;
n=++m;
n1=m++;
n–;
–n1;
n-=n1;
printf(“%d”, n);
return 0;
}
The output of the program is ______ : [GATE -2017]
a. 0
b. 1
c. 2
d. 3
Answer : a)
11. Consider the following C program.
#include<stdio.h>
#include<string.h>
int main () {
char* c = “GATECSIT2017”;
char* p = c;
printf(“%d”, (int) strlen (c + 2[p] – 6[p] – 1));
return 0;
}
The output of the program is __________. [GATE -2017]
a. 1
b. 2
c. 4
d. 6
Answer : b)
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