蓝桥杯—BASIC272n皇后问题(DFS)

#include
#include
using namespace std;
const int MAX_N &＃61; 8;
int n;
int ans &＃61; 0;
int c &＃61; 0;
int a[MAX_N][MAX_N];
int res1[3][MAX_N*2];//记录列&＃xff0c;左对角线&＃xff0c;右对角线是否有相同的皇后
int res2[3][MAX_N*2];//记录列&＃xff0c;左对角线&＃xff0c;右对角线是否有相同的皇后
void solve2(int cur) {if(cur &＃61;&＃61; n) { c&＃43;&＃43;; return; }for(int j &＃61; 0; j ) {if(a[cur][j] && !res2[0][j] && !res2[1][cur&＃43;j] && !res2[2][n&＃43;cur-j]) {res2[0][j] &＃61; 1; res2[1][cur&＃43;j] &＃61; 1; res2[2][n&＃43;cur-j] &＃61; 1;solve2(cur&＃43;1);res2[0][j] &＃61; 0; res2[1][cur&＃43;j] &＃61; 0; res2[2][n&＃43;cur-j] &＃61; 0;}}return;
}
void solve1(int cur) {if(cur &＃61;&＃61; n) {c &＃61; 0;solve2(0);ans &＃43;&＃61; c; return;}for(int j &＃61; 0; j ) {if(a[cur][j] && !res1[0][j] && !res1[1][cur&＃43;j] && !res1[2][n&＃43;cur-j]) {a[cur][j] &＃61; 0;res1[0][j] &＃61; 1; res1[1][cur&＃43;j] &＃61; 1; res1[2][n&＃43;cur-j] &＃61; 1;solve1(cur&＃43;1);a[cur][j] &＃61; 1;res1[0][j] &＃61; 0; res1[1][cur&＃43;j] &＃61; 0; res1[2][n&＃43;cur-j] &＃61; 0;}}return;
}
int main() {while(scanf("%d", &n) &＃61;&＃61; 1) {ans &＃61; 0;for(int i &＃61; 0; i )for(int j &＃61; 0; j ) scanf("%d", &a[i][j]);solve1(0);printf("%d\n", ans);}return 0;
}