zoj1259-Rails

#include<iostream>#include<stack>using namespace std;int knum[1001];int main(){int num,tnum;while(cin>>num&&num){while(1){int k=1,z=0;bool flag=false;stack<int> sta;sta.push(k++);bool fl= false;for(int i=0;i<num;i++){cin>>knum[i];if(knum[i]==0){fl=true;break;}}if(fl)break;for(int i=0;i<num;i++){int temp;temp=knum[z++];if(!sta.empty())if(sta.top()==temp)//栈顶{sta.pop();continue;}for(int j=0;k<=num;j++){if(k==temp)//压栈后有{k++;break;}sta.push(k++);}if(!sta.empty())if(temp<sta.top()){flag=true;break;}}if(flag)cout<<"No"<<endl;elsecout<<"Yes"<<endl;}cout<<endl;}return 0;}