BZOJ 5248: [2018多省省队联测]一双木棋(对抗搜索)

#include<cstdio>
#include<algorithm>
#include<cstring>
#include<map>
#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/hash_policy.hpp>
#define LL long long 
using namespace std;
using namespace __gnu_pbds;
const int MAXN = 11, INF = 1e9 + 10, base = 12;
inline int read() {
    char c = getchar(); int x = 0, f = 1; 
    while(c < '0' || c > '9') {if(c == '-') f = -1; c = getchar();}
    while(c >= '0' && c <= '9') x = x * 10 + c - '0', c = getchar();
    return x * f;
}
int N, M;
int A[MAXN][MAXN], B[MAXN][MAXN];
cc_hash_table<LL, int>mp;
int now[MAXN];
LL gethash() {
    LL x = 0;
    for(int i = 1; i <= N; i++) x = x * base + now[i];
    return x;
}
void push(LL x) {
    for(int i = N; i >= 1; i--) now[i] = x % base, x /= base;
}
int getnext() {
    int x = 0;
    for(int i = 1; i <= N; i++) x += now[i];
    return x & 1;
}
int dfs(LL sta) {
    if(mp.find(sta) != mp.end()) return mp[sta];
    push(sta);
    bool type = getnext();
    int ans = !type ? -INF : INF;
    for(int i = 1; i <= N; i++) {
        if(now[i] < now[i - 1]) {
            now[i]++;
            LL nxt = gethash();
            int val = dfs(nxt);
            ans = !type ? max(ans, val + A[i][now[i]]) : min(ans, val - B[i][now[i]]);
            now[i]--;
        }
    }
    return mp[sta] = ans;
}
main() {
    #ifdef WIN32
    freopen("a.in", "r", stdin);
    //freopen("a.out", "w", stdout);
    #else
    freopen("chess2018.in", "r", stdin);
    freopen("chess2018.out", "w", stdout);
    #endif
    N = read(); M = read();
    for(int i = 1; i <= N; i++)
        for(int j = 1; j <= M; j++)
            A[i][j] = read();
    for(int i = 1; i <= N; i++)
        for(int j = 1; j <= M; j++)
            B[i][j] = read();
    for(int i = 0; i <= N; i++) now[i] = M;
    mp[gethash()] = 0;
    dfs(0);
    printf("%d", mp[0]);
}