Submission #747940

#	Time	Username	Problem	Language	Result	Execution time	Memory
747940		MilosMilutinovic	Let's Win the Election (JOI22_ho_t3)	C++14	10 / 100	756 ms	8244 KiB

Main

#include <bits/stdc++.h>
using namespace std;
#define ldb long double
const int N = 505;
int n, k, a[N], b[N], ord[N];
ldb dp[N][N], ndp[N][N];
bool cmp(int i, int j) {
    int si = a[i] + (b[i] == -1 ? 1e8 : b[i]);
    int sj = a[j] + (b[j] == -1 ? 1e8 : b[j]);
    if (si != sj) return si < sj;
    else return a[i] > a[j];
}
int main() {
    scanf("%d%d", &n, &k);
    for (int i = 1; i <= n; i++) scanf("%d%d", &a[i], &b[i]), b[i] = (b[i] == -1 ? -1 : b[i] - a[i]);
    for (int i = 1; i <= n; i++) ord[i] = i;
    sort(ord + 1, ord + n + 1, cmp);
    for (int i = 0; i <= n + 1; i++)
        for (int j = 0; j <= n + 1; j++)
            dp[i][j] = 1e9;
    dp[0][1] = 0;
    for (int _i = 1; _i <= n; _i++) {
        int i = ord[_i];
        for (int j = 0; j <= n + 1; j++)
            for (int l = 0; l <= n + 1; l++)
                ndp[j][l] = dp[j][l];
        for (int j = 0; j <= n + 1; j++) {
            for (int l = 0; l <= n + 1; l++) {
                if (ndp[j][l] > 1e8) continue;
                dp[j + 1][l] = min(dp[j + 1][l], ndp[j][l] + (ldb) (a[i] + 0.0) / l);
                if (b[i] != -1) dp[j + 1][l + 1] = min(dp[j + 1][l + 1], ndp[j][l] + (ldb) (a[i] + b[i] + 0.0) / l);
            }
        }
    }
    ldb ans = 1e9;
    for (int i = 0; i <= n + 1; i++) ans = min(ans, dp[k][i]);
    printf("%.20Lf", ans);
    return 0;
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:14:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   14 |     scanf("%d%d", &n, &k);
      |     ~~~~~^~~~~~~~~~~~~~~~
Main.cpp:15:39: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   15 |     for (int i = 1; i <= n; i++) scanf("%d%d", &a[i], &b[i]), b[i] = (b[i] == -1 ? -1 : b[i] - a[i]);
      |                                  ~~~~~^~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 0 / 11
• Subtask 4: 0 / 12
• Subtask 5: 0 / 33
• Subtask 6: 0 / 11
• Subtask 7: 0 / 23