GATE Computer Science Programming and Data Structures Numerical Previous Year Questions

#include < stdio.h>  
void foo(int *p, int x){  
    *p=x;  
}  
int main(){  
    int *z;  
    int a = 20, b = 25;  
    z = &a;  
    foo(z,b);  
    printf("%d",a);  
    return 0;  
}  

The output of the given C program is ________. (Answer in integer)

The height of any rooted tree is defined as the maximum number of edges in the path from the root node to any leaf node.

Suppose a Min-Heap $T$ stores $32$ keys. The height of $T$ is ___________. (Answer in integer)

#include < stdio.h>  
int foo(int S[],int size){  
    if(size == 0) return 0;  
    if(size == 1) return 1;  
    if(S[0] != S[1]) return 1+foo(S+1,size-1);  
    return foo(S+1,size-1);  
}  
int main(){   
    int A[]={0,1,2,2,2,0,0,1,1};  
    printf("%d",foo(A,9));  
    return 0;  
}  

The value printed by the given C program is ______ . (Answer in integer)

Let LIST be a datatype for an implementation of linked list defined as follows:

typedef struct list {  
    int data;   
    struct list *next;  
} LIST;  

Suppose a program has created two linked lists, L1 and L2, whose contents are given in the figure below (code for creating L1 and L2 is not provided here). L1 contains 9 nodes, and L2 contains 7 nodes.

Consider the following C program segment that modifies the list L1. The number of nodes that will be there in L1 after the execution of the code segment is _______ .
(Answer in integer)

int find (int query, LIST *list) {  
    while (list != NULL){  
        if(list->data == query) return 1;  
        list = list->next;  
    }  
    return 0;  
}  
int main () {  
    ...  ...  ...  
    ptr1=L1; ptr2=L2;  
    while (ptr1->next != NULL){  
        query = ptr1->next->data;  
        if (find (query, L2))  
            ptr1->next = ptr1->next->next;  
        else ptr1 = ptr1->next;  
    }  
    ...  ...  ...  
    return 0;  
}  

Consider the following C program:

#include < stdio.h>  
int gate (int n) {  
    int d, t, newnum, turn;  
    newnum = turn = 0; t=1;  
    while (n>=t) t *= 10;  
    t /=10;  
    while (t>0) {  
        d = n/t;  
        n = n%t;  
        t /= 10;  
        if (turn) newnum = 10*newnum + d;  
        turn = (turn + 1) %2;  
    }  
    return newnum;  
}  
int main () {  
    printf ("%d", gate(14362));  
    return 0;  
}  

The value printed by the given C program is ______ . (Answer in integer)

In a double hashing scheme, h1(k) = k mod 11 and h2(k) = 1 + (k mod 7) are the auxiliary hash functions. The size m of the hash table is 11. The hash function for the i-th probe in the open address table is [h1(k) + i h2(k)] mod m. The following keys are inserted in the given order: 63, 50, 25, 79, 67, 24.

The slot at which key 24 gets stored is ________. (Answer in integer)

int x=126,y=105;  
do {  
    if(x>y) x=x-y;  
    else y=y-x;  
} while(x!=y);

printf("%d",x);  

The output of the given C code segment is _______. (Answer in integer)

Suppose the values 10, -4, 15, 30, 20, 5, 60, 19 are inserted in that order into an initially empty binary search tree. Let T be the resulting binary search tree. The number of edges in the path from the node containing 19 to the root node of T is ________. (Answer in integer)

Consider the following C program:

#include <stdio.h>

int main(){

    int a;

    int arr[5] = {30,50,10};

    int *ptr;

    ptr = &arr[0] + 1;

    a = *ptr;

    (*ptr)++;

    ptr++;

    printf("%d", a + (*ptr) + arr[1]);

    return 0;

}  

The output of the above program is ________. (Answer in integer)

Consider the following C program:

#include <stdio.h> 

int g(int n) {  
    return (n+10);  
}

int f(int n) {  
    return g(n*2);  
}

int main() {  
    int sum, n;  
    sum=0;  
    for (n=1; n<3; n++)  
        sum += g(f(n));  
    printf ("%d", sum);  
    return 0;  
}  

The output of the given C program is _______. (Answer in integer)