Last index element

#1

#include<bits/stdc++.h>
using namespace std;
int lastOccurence(int arr[],int i,int key)
{
if(i==0)
return -1;
if(arr[i]==key)
return i;
return lastOccurence(arr,i–,key);
}
int main()
{
int n;
cin >> n;
int arr[n];
for(int i=0;i<n;i++) cin>>arr[i];
int key;
cin >> key;
int ans = lastOccurence(arr,n-1,key);

if(ans)
  cout<<ans<<endl;
else
  cout<<"-1"<<endl;
return 0;

}

where am i doing wrong

#2

base case should be if(i<0){ return -1; }. key may be present at index=0;

#3

yeah made that change.the code is getting compiled but no output is coming

#4

@dare_devil_007
save your code at http://ide.codingblocks.com/ and then share here. I’ll check

#5

https://ide.codingblocks.com/s/224908 there you go!!

#6

@dare_devil_007
change “i–” in line 9 to “–i”. Your code will work.
Actually there is a difference between pre decrement and post decrement. Post decrement i.e i-- first uses the value of i and then decrement, so second argument of function always remains i. that’s why it is giving segmentation fault. Always use pre decrement in such case. pre decrement first decrease the value of i and then use it as function parameter.

#7

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