洛谷 P1281 书的复制

题目传送门

解题思路:

f[i][j]表示表示i本书分给j个人抄的最佳答案.最后贪心找答案.

AC代码:

#include<iostream>
#include<cstdio>
#include<cstring>

using namespace std;

int m,k,a[501],f[501][501],u,ansi[501],ansj[501],ans = 99999999,sum[501];

inline int min(int s,int d) {
    if(s >= d) return d;
    return s;
}

inline int max(int s,int d) {
    if(s >= d) return s;
    return d;
}

inline void find_answer() {
    int n = 0,end = m,id = k;
    for(int i = m;i >= 1; i--) {
        n += a[i];
        if(n > ans) {
            ansi[id] = i + 1;
            ansj[id] = end;
            end = i,n = 0,i++,id--;
        }
    }
    ansi[id] = 1;
    ansj[id] = end;
}

int main() {
    memset(f,0x3f3f3f,sizeof(f));
    scanf("%d%d",&m,&k);
    for(int i = 1;i <= m; i++) {
        scanf("%d",&a[i]);
        sum[i] = sum[i-1] + a[i];
        f[i][1] = sum[i];
    }
    for(int j = 2;j <= k; j++)
        for(int i = j;i <= m; i++)
            for(int k = j;k <= i; k++) {
                u = max(f[k-1][j-1],sum[i] - sum[k-1]);
                f[i][j] = min(f[i][j],u);
            }
    ans = f[m][k];
    find_answer();
    for(int i = 1;i <= k; i++)
        printf("%d %d
",ansi[i],ansj[i]);
    return 0;
}