Probably the easiest problem I tried to approach it in different way by AP sum. Like for each step our total sum will decrease by 2 and finally stops when we reach 0 sum.
#include<bits/stdc++.h>
using namespace std;
int main()
{
std::ios::sync_with_stdio(false);
int n;
cin>>n;
long long int arr[n];
long long int sum = 0;
for(int i=0;i<n;i++)
{
cin>>arr[i];
sum+=arr[i];
}
/*if(sum==0)
{
cout<<"YES"<<endl;
return 0;
}*/
long long int x = 0;
sum = sum+2;
x = sum/2;
if(sum%2==0)
cout<<"YES"<<endl;
else
cout<<"NO"<<endl;
return 0;
}
I am failing at 3 test case. Is this the wrong method or I am doing something wrong.. Thanks in advance
The algorithm is incorrect, consider input
The sequence can't be modified into all zeros, but (sum of elements + 2) is even and your algorithm outputs
YES
.