Submission #343394

#	Time	Username	Problem	Language	Result	Execution time	Memory
343394		ijxjdjd	Election (BOI18_election)	C++14	28 / 100	3071 ms	1076 KiB

election

#include <bits/stdc++.h>

using namespace std;

int main() {
    int N;
    cin >> N;
    vector<int> s(N);
    for (int i = 0; i < N; i++) {
        char c;
        cin >> c;
        if (c == 'C') {
            s[i] = 1;
        }
        else {
            s[i] = -1;
        }
    }
    int Q;
    cin >> Q;
    while (Q-->0) {
        int l, r;
        cin >> l >> r;
        l--, r--;
        unordered_set<int> touched;
        int cur = 0;
        for (int i = l; i <= r; i++) {
            cur += s[i];
            if (cur < 0) {
                cur = 0;
                touched.insert(i);
            }
        }
        cur = 0;
        for (int i = r; i >= l; i--) {
            if (!touched.count(i)) {
                cur += s[i];
                if (cur < 0) {
                    cur = 0;
                    touched.insert(i);
                }
            }
        }
        cout << touched.size() << '\n';
    }
    //        for (auto i : touched) {
    //            cerr << i << " ";
    //        }
//            int ans = (int)(1e9);
//            for (int j = 0; j < (1<<N); j++) {
//                int cur = 0;
//                bool flag = false;
//                for (int i = 0; i < N; i++) {
//                    if (!(j&(1<<i))) cur += s[i];
//                    if (cur < 0) flag = true;
//                }
//                cur = 0;
//                for (int i = N-1; i >= 0; i--) {
//                    if (!(j&(1<<i))) cur += s[i];
//                    if (cur < 0) flag = true;
//                }
//                if (!flag) {
//                    ans = min(ans, __builtin_popcount(j));
//                }
//            }
//            if (ans != touched.size()) {
//                for (int e : s) {
//                    cout << e << " ";
//                }
//                cout << '\n';
//                cout << ans << '\n';
//                for (int i : touched) {
//                    cout << i << " ";
//                }
//                break;
//            }
    return 0;
}

• Subtask 1: 28 / 28
• Subtask 2: 0 / 54
• Subtask 3: 0 / 18