0pts 求调

#include<bits/stdc++.h>
#define int long long
using namespace std;
bool ST;
inline int read(){
    int x = 0, f = 1;
    char ch = getchar();
    while(!isdigit(ch)){
        if(ch == '-') f = -1;
        ch = getchar();
    }
    while(isdigit(ch)){
        x = (x << 1) + (x << 3) + (ch ^ 48);
        ch = getchar();
    }
    return x * f;
}
int n, k, a[300005], s[300005], dp[300005][25];
inline int f(int x){return x * x;}
bool ED;
signed main(){
    n = read(), k = read();
    for(int i = 1; i <= n; i++) s[i] = s[i - 1] + (a[i] = read());
    memset(dp, 0x3f, sizeof(dp));
    dp[0][0] = 0;
    for(int j = 1; j <= k; j++){
        for(int i = 1; i <= n; i++){
            for(int t = 0; t < i; t++){
                dp[i][j] = min(dp[i][j], dp[t][j - 1] + f(s[i] - s[t]));
            }
        }
    }
    cout << f(k) * dp[n][k] - k * f(s[n]) << '\n';
    cerr << 1.0 * abs(&ED - &ST) / 1024 / 1024 << " MB" << '\n';
    return 0;
}