新手求调

#include<bits/stdc++.h>
using namespace std;
int n, d, m, a[50010];

bool check(int k) {
    int cnt = 0, pos = 0;
    for (int i = 1; i <= n + 1; i++) {
        if (a[i] - pos < k) {
            if (i == n + 1) return false; // 终点不能移除
            cnt++;
        } else {
            pos = a[i];
        }
    }
    return cnt <= m;
}

int main() {
    cin >> d >> n >> m;
    for (int i = 1; i <= n; i++) {
        cin >> a[i];
    }
    a[n + 1] = d;

    int l = 1, r = d, mid, ans = 0;
    while (l <= r) {
        mid = (l + r) / 2;
        if (check(mid)) {
            l = mid + 1;
            ans = mid;
        } else {
            r = mid - 1;
        }
    }
    cout << ans;
    return 0;
}