different outputs in vs code and online compiler, for c++ recursion

Question

I've tried to write a code on linear search using recursion. the program stores all occurrences of target in a vector. the code is giving incorrect output on vs code. but it is working correctly on online compilers.

#include<iostream>
#include<vector>
using namespace std;

vector<int> linearsearch(int *arr, int target, int size){
    static vector<int> v;
    static int i=0;
    if(arr[i]==target)
    v.push_back(i);
    if(i>=size)
    return v;
    i++;

   return linearsearch(arr,target, size);

}
int main(){
    int arr[7]={3,7,7, 8, 7, 0, 5};
    
    int target=7;
   vector<int> q=linearsearch(arr,target, 7);
    cout<<"printing all occurences of target"<<endl;
    for(int j=0;j<q.size();j++){
        cout<<q[j]<<endl;
    }
    return 0;
}

online compilers are correctly printing 1 2 4. but vs code is printing 1 2 4 7.

Your code leads to undefined behavior. You check `i>=size` too late, after the access `arr[i]` with an invalid index. — 273K, Oct 08 '22 at 05:26
Aside: do not use static variables to pass data between invocations of a recursive function (or indeed any functions). — n. m. could be an AI, Oct 08 '22 at 05:57
Read this: https://en.cppreference.com/w/cpp/language/ub - including the articles linked at the end. — Jesper Juhl, Oct 08 '22 at 07:08

different outputs in vs code and online compiler, for c++ recursion

0 Answers0