Uva10817 Headmaster's Headache

https://odzkskevi.qnssl.com/b506a3c20adad78678917d1ff4c9b953?v=1508327485

【题解】

dp[i][S1][S2]表示前i个教师选/不选已经决策完，当前有一个老师教的课程为S1，两个老师教的课程为S2，还需要的最小价值

答案为dp[0][0][0]

转移即可

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <algorithm>
#include <sstream>
#include <vector>
#include <string>
#include <cmath> 
#define min(a, b) ((a) < (b) ? (a) : (b))
#define max(a, b) ((a) > (b) ? (a) : (b))

inline void swap(int &a, int &b)
{
    int tmp = a;a = b;b = tmp;
}

inline void read(int &x)
{
    x = 0;char ch = getchar(), c = ch;
    while(ch < '0' || ch > '9')c = ch, ch = getchar();
    while(ch <= '9' && ch >= '0')x = x * 10 + ch - '0', ch = getchar();
    if(c == '-')x = -x;
}

const int INF = 0x3f3f3f3f;
const int MAXN = 100 + 10;
const int MAXM = 20 + 5;
const int MAXS = 8;

struct Edge
{
    int u,v,nxt;
    Edge(int _u, int _v, int _nxt){u = _u;v = _v;nxt = _nxt;}
    Edge(){}
}edge[MAXN << 1];
int head[MAXN], cnt;

inline void insert(int a, int b)
{
    edge[++cnt] = Edge(a,b,head[a]);
    head[a] = cnt;
}

int m,n,s,c[MAXN + MAXM],a[MAXN + MAXM],dp[MAXN + MAXM][1 << MAXS][1 << MAXS],ma;
std::string ch;

int DP(int i, int s0, int s1, int s2)
{
    if(i > n + m) return s2 == ma - 1 ? 0 : INF;
    if(dp[i][s1][s2] >= 0)return dp[i][s1][s2];
    dp[i][s1][s2] = INF;
    if(i > m) dp[i][s1][s2] = DP(i + 1, s0, s1, s2);
    int tmp1 = s0 & a[i], tmp2 = s1 & a[i];
    dp[i][s1][s2] = min(dp[i][s1][s2], DP(i + 1, s0^tmp1, (s1 ^ tmp2) | tmp1, s2 | tmp2) + c[i]);
    return dp[i][s1][s2];
}

int main()
{
    while(scanf("%d %d %d", &s, &m, &n) != EOF && n + m + s)
    {
        std::cin.get(); 
        memset(dp, -1, sizeof(dp));
        memset(a, 0, sizeof(a));
        int tmp;
        for(register int i = 1;i <= m + n;++ i) 
        {
            getline(std::cin, ch);
            std::stringstream cc(ch);
            cc >> c[i];
            a[i] = 0;
            while(cc >> tmp)
                a[i] |= 1 << (tmp - 1);
        }
        ma = 1 << s;
        printf("%d
", DP(1, ma - 1, 0, 0));
    }
    return 0;
}