51nod 1875 丢手绢

预处理打表

#include<bits/stdc++.h>using namespace std;int main(){long long i,j,k,kk,g,ans[20],tmp,flag,last,used[30],now;for(i=1;i<=13;i++){ans[i]=i+1;for(;;){now=1;flag=1;memset(used,0,sizeof(used));for(j=1;j<=i&&flag;j++){tmp=(ans[i]-1)%(i+i-j+1);for(k=now;;k=(k+1>i+i?1:k+1)){if(used[k])continue;if(tmp==0){used[k]=1;if(k<=i){flag=0;break;}for(kk=k;;kk=(kk+1>i+i?1:kk+1)){if(!used[kk])break;}now=kk;break;}elsetmp--;}}if(flag)break;ans[i]++;}}while(~scanf("%lld",&g)&&g){printf("%lld\n",ans[g]);}}