Codeforces Round 653 (Div. 3) 1374D - Zero Remainder Array Solution

 Problem Link  :  https://codeforces.com/problemset/problem/1374/D

Solution in C++:

1. /// La ilaha illellahu muhammadur rasulullah
2. ///******Bismillahir-Rahmanir-Rahim******///
3. /// Abul Hasnat Tonmoy
4. /// Department of CSE,23rd batch
5. /// Islamic University,Bangladesh
6. ///**********ALLAH IS ALMIGHTY************///
7. #include <bits/stdc++.h>
8. using namespace std;
9. using ll = long long ;
10. int main() {
11. ios_base::sync_with_stdio(0);
12. cin.tie(0);
13. ll t ;
14. cin >> t ;
15. while ( t-- ) {
16. ll n , k ;
17. cin >> n >> k ;
18. ll a[n+9] , b[n+9] ;
19. for ( ll i = 1 ; i <= n ; i++ ) {
20. cin >> a[i] ;
21. a[i] = a[i] % k ;
22. if ( a[i] != 0 ) a[i] = k - a[i] ;
23. }
24. sort( a + 1 , a + n + 1 ) ;
25. ll ans ;
26. ans = a[1] , b[1] = a[1] ;
27. for ( ll i = 2 ; i <= n ; i++ ) {
28. if (a[i] == 0 ) continue ;
29. if ( a[i-1] == a[i] ) b[i] = b[i-1] + k ;
30. else b[i] = a[i] ;
31. ans = max ( ans , b[i]) ;
32. }
33. if ( ans != 0 ) cout << ans + 1 << endl ;
34. else cout << ans << endl;
35. }
36. }