Submission #921819

#	Time	Username	Problem	Language	Result	Execution time	Memory
921819		Alebn	Fancy Fence (CEOI20_fancyfence)	C++14	28 / 100	1050 ms	3924 KiB

fancyfence

#include <bits/stdc++.h>
#define int long long
 
using namespace std;
 
const int MOD = 1e9+7, INV = 250000002;
 
int f(int n, int m) {
    return n * m % MOD * (n + 1) % MOD * (m + 1) % MOD * INV % MOD;
}
 
signed main() {
    //input and sum
    int n;
    cin >> n;
    vector<int> h(n), w(n);
    for(int i = 0; i < n; i++) cin >> h[i];
    for(int i = 0; i < n; i++) cin >> w[i];
    //linearily go over and compute result
    int res = 0;
    vector<int> hSorted;
    set<int> st;
    for(int i = 0; i < n; i++) {
        if(!st.count(h[i])) {
            hSorted.push_back(h[i]);
            st.insert(h[i]);
        }
    }
    sort(hSorted.begin(), hSorted.end());
    for(int i = 0; i < hSorted.size(); i++) {
        int consecutiveW = 0, minH = INT_MAX;
        for(int j = 0; j < n; j++) {
            if(h[j] < hSorted[i]) {
                //cout << minH << " " << consecutiveW << "\n";
                res = (res + f(minH, consecutiveW)) % MOD;
                if(i != 0) res = (res - f(hSorted[i-1], consecutiveW)) % MOD;
                if(res < 0) res = (res + 10000000070000000) % MOD;
                consecutiveW = 0, minH = INT_MAX;
            } else {
                consecutiveW = (consecutiveW + w[j]) % MOD;
                minH = min(minH, h[j]);
            }
        }
        //cout << minH << " " << consecutiveW << "\n";
        res = (res + f(minH, consecutiveW)) % MOD;
        if(i != 0) res = (res - f(hSorted[i-1], consecutiveW)) % MOD;
        if(res < 0) res = (res + 10000000070000000) % MOD;
        //cout << res << " " << i << "r\n";
    }
    //cout << h[n-1] << " " << m << "\n";
    cout << res << "\n";
}

Compilation message (stderr)

fancyfence.cpp: In function 'int main()':
fancyfence.cpp:30:22: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   30 |     for(int i = 0; i < hSorted.size(); i++) {
      |                    ~~^~~~~~~~~~~~~~~~

• Subtask 1: 0 / 0
• Subtask 2: 0 / 12
• Subtask 3: 13 / 13
• Subtask 4: 15 / 15
• Subtask 5: 0 / 15
• Subtask 6: 0 / 18
• Subtask 7: 0 / 27