HDU 1426 Sudoku Killer(搜索)

题目链接：http://acm.hdu.edu.cn/showproblem.php?pid=1426

题意很明确，让你解一个9*9的数独。

DFS即可。

#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>
#include <functional>

using namespace std;

#define REP(i,n)        for(int i(0); i <  (n); ++i)
#define rep(i,a,b)        for(int i(a); i <= (b); ++i)
#define dec(i,a,b)        for(int i(a); i >= (b); --i)
#define for_edge(i,x)        for(int i = H[x]; i; i = X[i])

#define LL    long long
#define ULL    unsigned long long
#define MP    make_pair
#define PB    push_back
#define FI    first
#define SE    second
#define INF    1 << 30

const int N    =            +    ;
const int M    =            +    ;
const int Q    =            +    ;
const int A    =            +    ;

struct node{
    int x, y;
} d[Q];

char ch;

bool a[A][A];
int f[A][A], r[A][A], c[A][A], v[A][A];
bool rr[A][A], cc[A][A], vv[A][A];
int num;

inline void print(){
    rep(i, , ){rep(j, , ) printf("%d ", f[i][j]); printf("%d", f[i][]); putchar();}
}

void dfs(int now){
    if (now > num){ print(); return ;}
    int x = d[now].x, y = d[now].y;

    rep(i, , ){
        if (vv[v[x][y]][i]) continue;
        if (cc[c[x][y]][i]) continue;
        if (rr[r[x][y]][i]) continue;
        f[x][y] = i;
        vv[v[x][y]][i] = true;
        cc[c[x][y]][i] = true;
        rr[r[x][y]][i] = true;
        dfs(now + );
        f[x][y] = ;
        vv[v[x][y]][i] = false;
        cc[c[x][y]][i] = false;
        rr[r[x][y]][i] = false;
    }

}

int main(){
#ifndef ONLINE_JUDGE
    freopen("test.txt", "r", stdin);
    freopen("test.out", "w", stdout);
#endif

    rep(i, , ) rep(j, , ) v[i][j] = ;
    rep(i, , ) rep(j, , ) v[i][j] = ;
    rep(i, , ) rep(j, , ) v[i][j] = ;
    rep(i, , ) rep(j, , ) v[i][j] = ;
    rep(i, , ) rep(j, , ) v[i][j] = ;
    rep(i, , ) rep(j, , ) v[i][j] = ;
    rep(i, , ) rep(j, , ) v[i][j] = ;
    rep(i, , ) rep(j, , ) v[i][j] = ;
    rep(i, , ) rep(j, , ) v[i][j] = ;
    rep(i, , ) rep(j, , ) r[i][j] = i, c[i][j] = j;
    int Case = ;

    //rep(i, 1, 9){rep(j, 1, 9) printf("%d ", c[i][j]); putchar(10); }
    while (~scanf("%c ", &ch)){
        if (Case) puts(""); else Case = ;
    //    memset(a, false, sizeof a);
        memset(f, , sizeof f);
        memset(cc, false, sizeof cc);
        memset(vv, false, sizeof vv);
        memset(rr, false, sizeof vv);
        memset(d, , sizeof d);
        num = ;
        if (ch == '?'){
               f[][] = ;
               d[++num].x = , d[num].y = ;
        }
        else{
                   int np = (int)ch - ;
                f[][] = np;
                cc[c[][]][np] = true;
                vv[v[][]][np] = true;
                rr[r[][]][np] = true;
        }

        rep(cnt, , ){
            scanf("%c ", &ch);
            int x = (cnt - ) /  + , y = (cnt - ) %  + ;
            if (ch == '?'){
                   f[x][y] = ;
                d[++num].x = x, d[num].y = y;
            }
            else{
                int np = (int)ch - ;
                f[x][y] = np;
                cc[c[x][y]][np] = true;
                vv[v[x][y]][np] = true;
                rr[r[x][y]][np] = true;

            }
        //rep(i, 1, 9){rep(j, 1, 9) printf("%d ", f[i][j]); putchar(10);}
        }
        dfs();
    }

    return ;

}