#include <iostream>
int reverse(int input)
{
int last_digit;
int reversedNum = 0;
while (input != 0) {
last_digit = input % 10;
reversedNum = reversedNum * 10 + last_digit;
input = input / 10;
}
return reversedNum;
}
int main(){
for(int i = 0; i < 10000; ++i){
cout << i << " : " << reverse(i) << " ";
if( i && i % 10 == 0 ) cout << endl;
}
return 0;
}