Submission #731767

#	Time	Username	Problem	Language	Result	Execution time	Memory
731767		Trunkty	Modsum (NOI12_modsum)	C++14	25 / 25	2 ms	332 KiB

modsum

#include <bits/extc++.h>
using namespace std;
typedef long long ll;
#define int ll

int n,ans,tot;
int arr[1005];
int nex=1;

void dfs(int x){
    if(x==nex){
        int z = (tot*tot)%5;
        ans += (z*z+2*z)%5+1;
        return;
    }
    for(int j=0;j<=arr[x];j++){
        tot += j;
        dfs(x+1);
        tot -= j;
    }
}

signed main(){
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
    cin >> n;
    for(int i=1;i<=n;i++){
        int a,b;
        cin >> a >> b;
        tot += a;
        if(a!=b){
            arr[nex] = b-a;
            nex++;
        }
    }
    dfs(0);
    cout << ans << "\n";
	return 0;
}

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 5 / 5
• Subtask 4: 5 / 5
• Subtask 5: 5 / 5