SGU 109 Magic of David Copperfield II

构造策略：

先走n步 把大于与左上角曼哈顿距离的格子删掉 因为这些格子是达不到的（曼哈顿距离：横坐标之差+纵坐标之差）然后就要处理奇偶性了：如果为偶数，则+1，转换为奇数；否则+2。设一个dist为每次的曼哈顿距离与当前点的差。一层一层向里删除格子，知道这个差dist<=2，游戏结束，玩家已经被困在中间格子内。

AC代码：

#include <cstdio>#include <cstring>#include <iostream>#include <algorithm>int n;int main(){    scanf("%d",&n);    printf("%d",n);        for (int i=1;i<=n;i++)        for (int j=1;j<=n;j++)            if (i-1+j-1>n) printf(" %d",(i-1)*n+j);    printf("\n");        int dist = n+2;    int now = n;    while (dist > 2){        now++;        while (now % 2 == 0) now++;        printf("%d",now);        for (int i=1;i<=n;i++)            for (int j=1;j<=n;j++)                if (i+j == dist) printf(" %d",(i-1)*n+j);        printf("\n");        dist--;    }    //system("pause");    return 0;}