思路就是暴力模拟，但有 3 个点 WA 了，求大佬指正 QwQ

#include <bits/stdc++.h>
using namespace std;

int n, w, a[100100], b[100100], ans = INT_MAX, cnt[100100];

int main() {
    scanf("%d%d", &n, &w);
    for (int i = 0; i < n; ++i) {
        scanf("%d", &a[i]);
        ++cnt[a[i]];
    }
    if (n == 1) {
        puts("0");
        return 0;
    }
    int diff = a[1] - a[0];
    bool flag = 1;
    for (int i = 2; i < n; ++i) {
        if ((a[i] - a[i - 1]) != diff) {
            flag = 0;
            break;
        }
    }
    if (flag && diff >= 0) {
        puts("0");
        return 0;
    }
    int maxcnt = 0;
    for (int i = 0; i < n; ++i) {
        maxcnt = max(maxcnt, cnt[a[i]]);
    }
    ans = n - maxcnt;
    for (int i = 1; i <= ceil(w / double(n - 1)); ++i) {
        int op = 0;
        flag = 1;
        memcpy(b, a, sizeof(a));
        for (int j = 1; j < n; ++j) {
            if ((b[j] - b[j - 1]) != i) {
                b[j] = b[j - 1] + i;
                if (b[j] > w) {
                    flag = 0;
                    break;
                }
                ++op;
            }
        }
        if (flag) {
            ans = min(ans, op);
        }
    }
    printf("%d", ans);
    return 0;
}