GATE CS 2025 Set 1 — Question 61
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Programming & Data Structures → C Programming → Arrays & Strings in C
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Question
#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;
}
Correct answer
5 to 5
Solution
The function is a recursive function that processes an array of a given .
- Base Cases:
- If , it returns .
- If , it returns .
- Recursive Step:
- If the first element is not equal to the second element , it returns .
- Otherwise, it returns .
1.: . Since , returns .
2.: . Since , returns .
3.: . Since , returns .
4.: . Since , returns .
5.: . Since , returns .
6.: . Since , returns .
7.: . Since , returns .
8.: . Since , returns .
9.: , returns .
Summing the values: .Alternatively, the contiguous blocks of identical elements are: , , , , and . There are such blocks, so the function returns .Continue learning with Success Tracker
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