# include<iostream> # include<cmath> using namespace std; int main(){ int a; cin>>a; for(int i = 1; i <= a; i++){ int b = 1;//几位数 while((int)(i/pow(10.0, b))>0)b++; int m = 0,n = b+1;//开头，结尾 while(true){ m++; n--; int _m = (int)(i/pow(10.0, b-m))-(int)(i/pow(10.0, b-m+1))*10; int _n = (int)(i/pow(10.0, b-n))-(int)(i/pow(10.0, b-n+1))*10; if(_m != _n){ break; } if(m>=n){ cout<<i<<endl; break; } } } return 0; }