"use strict";
const Main = (input) =>{
   let xs = input.trim().split(' ');
   let result = "";    
     for(let i =0; i<xs.length; i++){
   	    result +=xs[i].match(/[A-Z]/);
      }
   console.log(result);
}
Main(require('fs').readFileSync('/dev/stdin','utf8'));