Submission #1060248

#	Time	Username	Problem	Language	Result	Execution time	Memory
1060248		anango	Gift Exchange (JOI24_ho_t4)	C++17	50 / 100	2594 ms	11444 KiB

Main

#include <bits/stdc++.h>
#define int long long
using namespace std;
int INF = 1LL<<30;



signed main() {
    int local = 0;
    if (local) {
        // for getting input from input.txt
        freopen("input.txt", "r", stdin);
        // for writing output to output.txt
        freopen("output.txt", "w", stdout);
    }
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    int n; cin >> n;
    vector<int> ar(n); for (int i=0; i<n; i++) cin >> ar[i];
    vector<int> br(n); for (int i=0; i<n; i++) cin >> br[i];
    /*for (int i=0; i<n; i++) {
        ar[i]--; br[i]--;
    }*/
    int q; cin >> q;
    while (q--) {
        int l,r; cin >> l >> r; l--; r--;
        vector<pair<int,int>> endpoints;
        for (int i=l; i<=r; i++) {
            endpoints.push_back({ar[i],-(i+1)});
            endpoints.push_back({br[i],(i+1)});
        }
        sort(endpoints.begin(), endpoints.end());
        int fail = 0;
        int ct = 0;
        for (int i=0; i<endpoints.size(); i++) {
            if (endpoints[i].second<0) ct--;
            else ct++;
            //cout << i <<" " << endpoints[i].first <<" " << endpoints[i].second <<" " << ct << endl;
            if (ct==0 && i!=0 && endpoints[i].second+endpoints[i-1].second==0) {
                fail=1;
            }
        }
        if (fail) {
            cout << "No" << endl;
        }
        else {
            cout << "Yes" << endl;
        }
    }
    
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:35:24: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   35 |         for (int i=0; i<endpoints.size(); i++) {
      |                       ~^~~~~~~~~~~~~~~~~
Main.cpp:12:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   12 |         freopen("input.txt", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:14:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   14 |         freopen("output.txt", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 4 / 4
• Subtask 2: 5 / 5
• Subtask 3: 10 / 10
• Subtask 4: 31 / 31
• Subtask 5: 0 / 8
• Subtask 6: 0 / 12
• Subtask 7: 0 / 18
• Subtask 8: 0 / 12