# Help me in solving OG problem

### My issue

Can anyone help??
Don’t see the code, I first implemented it using the for loop in which, I iterated over every integer but it was wrong
so i found another approach in which I calculated the sum of 1-9 and then multiply it with the number i.e. modulus of the given number and then adding the remaining.

Actually I can’t express it in words nor I was successful in writing it as code,
If you have a code for this question, then please provide it.

### My code

``````#include <bits/stdc++.h>
using namespace std;

// int sumOfDigits(long long int n) {
//     int sum = 0;
//     while (n > 0) {
//         sum += n % 10;
//         n /= 10;
//     }
//     return sum;
// }

// int origin(long long int n) {
//     while (n >= 10) {
//         n = sumOfDigits(n);
//     }
//     return n;
// }

// int main() {
//     int t;
//     cin >> t;
//     while (t--) {
//         long long int n;
//         cin >> n;
//         long long int total = 0;
//         for (long long int i = 1; i <= n; i++) {
//             total += origin(i);
//         }
//         cout << total << endl;
//     }
//     return 0;
// }

int origin(int n){
int count = 0;
for (int i=1; i<=n; i++){
count+=i;
}
// cout << count << endl;
return count;
}
// a=9, b=45
int main(){
int t;
cin >> t;
while (t--){
long long int n;
cin >> n;
int a,b;
long long int total = 0;
// while (n<=10){
// a = n - (n%9);
a=9;
int first = n%a;
// b = (n/9) * 45;
b=45;
int second = n - first*a;
total += (first*b);
// cout << total << endl;
total += origin(second);
// }
cout << total << endl;
}
}
``````

Problem Link: Origin Practice Coding Problem - CodeChef

``````#include <bits/stdc++.h>
using namespace std;

int main() {
int t;
cin>>t;
while(t--){
long long n;
cin>>n;
long long rem = n%9;
long long mul = n/9;
long long sum = 0;
for(int i=1;i<=rem;i++){
sum+=i;
}
sum += mul*45;
cout<<sum<<endl;
}

}

``````