Submission #986936

#	Time	Username	Problem	Language	Result	Execution time	Memory
986936		Alebn	Sure Bet (CEOI17_sure)	C++14	100 / 100	154 ms	3664 KiB

sure

#include <bits/stdc++.h>

using namespace std;

int n;
vector<double> a, b;

bool srt(double x, double y) {
    if(x == 0) return true;
    if(y == 0) return false;
    return x > y;
}

int main() {
    cin >> n;
    a = vector<double>(n + 1), b = vector<double>(n + 1);
    for(int i = 1; i <= n; i++) cin >> a[i] >> b[i];
    sort(a.begin(), a.end(), srt);
    sort(b.begin(), b.end(), srt);
    for(int i = 1; i <= n; i++) {
        a[i] += a[i - 1];
        b[i] += b[i - 1];
    }
    //
    double res = 0;
    for(int i = 0; i <= n; i++) {
        int l = 0, r = n + 1, mid, ans;
        while(l<=r) {
            mid = (l + r) / 2;
            if(b[mid] <= a[i]) {
                ans = mid;
                l = mid + 1;
            } else r = mid - 1;
        }
        res = max(res, min(a[i], b[ans]) - i - ans);
        if(a[i] != b[ans] && ans != n) res = max(res, min(a[i], b[ans + 1]) - i - ans - 1);
        //cout << i << " " << ans << " " << res << "\n";
    }
    for(int i = 0; i <= n; i++) {
        int l = 0, r = n + 1, mid, ans;
        while(l<=r) {
            mid = (l + r) / 2;
            if(a[mid] <= b[i]) {
                ans = mid;
                l = mid + 1;
            } else r = mid - 1;
        }
        res = max(res, min(b[i], a[ans]) - i - ans);
        if(b[i] != a[ans] && ans != n) res = max(res, min(b[i], a[ans + 1]) - i - ans - 1);
        //cout << i << " " << ans << " " << res << "\n";
    }
    cout << fixed << setprecision(4) << res << "\n";
}

Compilation message (stderr)

sure.cpp: In function 'int main()':
sure.cpp:49:27: warning: 'ans' may be used uninitialized in this function [-Wmaybe-uninitialized]
   49 |         if(b[i] != a[ans] && ans != n) res = max(res, min(b[i], a[ans + 1]) - i - ans - 1);
sure.cpp:36:27: warning: 'ans' may be used uninitialized in this function [-Wmaybe-uninitialized]
   36 |         if(a[i] != b[ans] && ans != n) res = max(res, min(a[i], b[ans + 1]) - i - ans - 1);

• Subtask 1: 20 / 20
• Subtask 2: 40 / 40
• Subtask 3: 40 / 40