Shoing tle and wrong answer for some cases

#1

#include <bits/stdc++.h>
#define ll long long

using namespace std;

int counti(int arr[],int n,int k){
int mod[k];
memset(mod,0,sizeof(mod));
ll cumsum=0;

for(int i=0;i<n;i++){
    cumsum+=arr[i];
    mod[(cumsum%k)+k%k]++;
}
int result=0;
for(int i=0;i<k;i++)
    if(mod[i]>1)result+=(mod[i]*(mod[i]-1))/2;
result+=mod[0];
return result;

}
int main(){
int t;cin>>t;
while(t–){
int n;cin>>n;int arr[n];

            for(int i=0;i<n;i++)cin>>arr[i];
        cout<<counti(arr,n,n)<<endl;

}}

#2

Hello @argus i have corrected your code :

if you have any doubt you can ask here:
Happy Learning!!

#3

hey, thank you very much for always resolving my doubts

#4

but what was bug in my code this time

#5

@argus
mod[0]=1;// you have to count for sum 0 as well so for sum=0 make the count as 1
and this as well:
mod[((cumsum%k)+k)%k]++; //you are doing this in this way mod[(cumsum%k)+k%k]++i.e k%k for negative terms it would not evaluate the same way because everytime k%k will give you reamainder as 0.so you have to take bracket like the way i have made change:


Happy Learning!!

#6

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