Submission #530526

#	Time	Username	Problem	Language	Result	Execution time	Memory
530526		4fecta	Cake 3 (JOI19_cake3)	C++17	24 / 100	186 ms	67888 KiB

cake3

#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define int ll
#define ld long double
#define pii pair<int, int>
#define f first
#define s second
#define boost() cin.tie(0), cin.sync_with_stdio(0)

const int MN = 2005;

int n, m, dp[MN][MN];
pii a[MN];

void solve(int j, int l, int r, int p1, int p2) {
    if (l > r) return;
    int mid = (l + r) >> 1, opt = 0;
    for (int p = p1; p <= min(p2, mid - 1); p++) {
        if (dp[mid][j] < dp[p][j - 1] + a[mid].s - a[mid].f + a[p].f) {
            dp[mid][j] = dp[p][j - 1] + a[mid].s - a[mid].f + a[p].f;
            opt = p;
        }
    }
    solve(j, l, mid - 1, p1, opt), solve(j, mid + 1, r, opt, p2);
}

int32_t main() {
    boost();

    cin >> n >> m;
    for (int i = 1; i <= n; i++) cin >> a[i].s >> a[i].f, a[i].f *= 2;
    sort(a + 1, a + n + 1);
    int ans = -0x3f3f3f3f;
    memset(dp, -0x3f, sizeof(dp));
    for (int i = 1; i <= n; i++) dp[i][1] = a[i].s;
    for (int j = 2; j <= m; j++) solve(j, 1, n, 1, n);
    for (int i = 1; i <= n; i++) ans = max(ans, dp[i][m]);
    printf("%lld\n", ans);

    return 0;
}

• Subtask 1: 5 / 5
• Subtask 2: 19 / 19
• Subtask 3: 0 / 76