HDU 2553 (n Queen) (DFS)

http://acm.hdu.edu.cn/showproblem.php?pid=2553

I represents rows, Map[i] represents columns, and then uses DFS traversal backtracking

You can refer to this article:

http://blog.csdn.net/cambridgeacm/article/details/7703739

1#include <iostream>2#include <string>3#include <cstring>4#include <cstdlib>5#include <cstdio>6#include <cmath>7#include <algorithm>8#include <stack>9 using namespacestd;Ten  One #defineMEM (A, B) memset (A,b,sizeof (a)) A  - BOOLused[ the]; - //i means row, Map[i] represents the column the intmap[ the]; - intsol[ the]; -  - intAns,n; +  -  + voidDfsintk) A { at           inti,j; -  -           //Judging the end -           if(k==n+1) -           { -ans++; in                     return; -           } to  +            for(i =1; i<=n;i++) -           { the                     if(!Used[i]) *                     { $MAP[K] =i;Panax Notoginseng                               BOOLFlag =true; -  the                               //Whether it's on a diagonal line +                                for(j=1; j<=k-1; j + +) A                               { the                                         if((map[k]-map[j]) = = (K-j) | | (Map[k]-map[j]) = = (J-k)) +                                         { -Flag =false; $                                                   Break; $                                         } -                               } -                               if(flag) the                               { -Used[i] =true;WuyiDFS (k +1); the                                         //not found, release used -                                         //Backtracking WuUsed[i] =false; -                               } About                     } $           } - } -  -  A intMain () + { the           intt,i; -           //save is because there may be duplicate data in the background, the efficiency is the same for a single time $            for(i =1; i<=Ten; i++) the           { theMEM (Used,false); theMEM (Map,0); then =i; -Ans =0; inDfs1); theSol[i] =ans; the           } About  the      while(~SCANF ("%d", &n) &&N) the     { theprintf"%d\n", Sol[n]); +     } -     return 0; the}

HDU 2553 (n Queen) (DFS)