C Programming

Consider the C code fragment given below.

typedef struct node {
  int data;
  node* next;
} node;

void join(node* m, node* n){
  node* p = n;
  while(p->next != NULL) {
    p = p->next;
  }
  p->next = m;
}

Assuming that m and n point to valid NULL-terminated linked lists, invocation of join will

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(sizeof(int));
             if(NULL == x) return;
             x = assignval(x,10);
       }
      printf("%d\n", *x);
      free(x);
}

The code suffers from which one of the following problems:

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

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:

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 ________.

The output of executing the following C program is ________.

#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(; i > 0; i--) {
        x = x + total(i);
    }
    printf("%d\n", x);
}

Match the following:

(P) static char var;          (i)   Sequence of memory locations to store addresses
(Q) m = malloc(10);           (ii)  A variable located in data section of memory
    m = NULL;
(R) char *ptr[10];            (iii) Request to allocate a CPU register to store data
(S) register int var1;        (iv)  A lost memory which cannot be freed

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

Consider the C program fragment below which is meant to divide x by 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)?

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;
      int i;

      while (done == 0) {
            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 ________.

Consider the following C Program.

#include<stdio.h>
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 ________.

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 ________.

What is the return value of f(p,p), if the value of p is initialized to 5 before the call? Note that the first parameter is passed by reference, whereas the second parameter is passed by value.

int f (int &x, int c) {
   c = c - 1;
   if (c==0) return 1;
   x = x + 1;
   return f(x,c) * x;
}