Submission #948867

#	Time	Username	Problem	Language	Result	Execution time	Memory
948867		Irate	Modsum (NOI12_modsum)	C++14	25 / 25	1 ms	600 KiB

modsum

#include <bits/stdc++.h>
using namespace std;
const int mxN = 1005;
pair<int, int> ranges[mxN];
int dp[mxN][5], n;
int f(int indx, int mod){
    if(indx == n)return (mod * mod % 5) * (mod * mod + 2) % 5 + 1;
    if(dp[indx][mod] != -1)return dp[indx][mod];
    int res = 0;
    for(int i = 0;i < 5;++i){
        int cnt = 0;
        cnt = (ranges[indx].second - i) / 5;
        if(ranges[indx].first - i - 1 > 0)cnt -= (ranges[indx].first - i - 1) / 5;
        for(int j = ranges[indx].first - i;j <= min(0, ranges[indx].second - i);++j){
            cnt += (j % 5 == 0);
        }
        if(cnt)res += cnt * f(indx + 1, (mod + i) % 5);
    }
    return dp[indx][mod] = res;
}
int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cin >> n;
    for(int i = 0;i < n;++i){
        cin >> ranges[i].first >> ranges[i].second;
    }
    for(int i = 0;i < mxN;++i){
        for(int j = 0;j < 5;++j){
            dp[i][j] = -1;
        }
    }
    cout << f(0, 0);
}

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