output_description: Print the answer.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      s_1 s_2 s_3
attempt: #include <iostream>
  #include <algorithm>
  #include <vector>
  #include <string>
  #include <map>
  #include <climits>
  #include <math.h>
  #include <utility>
  using namespace std;
  
  typedef long long ll;
  typedef vector<bool> vb;
  typedef vector<char> vc;
  typedef vector<long long> vll;
  typedef vector<int> vi;
  typedef vector<string> vs;
  typedef vector<vector<bool>> vvb;
  typedef vector<vector<int>> vvi;
  
  #define rep(i,n) for(int (i)=0;(i)<(n);(i)++)
  #define all(a) a.begin(),a.end()
  
  int main() {
  	vs s(3);
  	rep(i, 3)cin >> s.at(i);
  	rep(i, 3) {
  		cout << char(s.at(i).at(0) - 32);
  	}
  	cout << endl;
  	return 0;
  }
  
problem_description: Statement
  
  You are given three words s_1, s_2 and s_3, each composed of lowercase English
  letters, with spaces in between. Print the acronym formed from the uppercased
  initial letters of the words.
samples: [{"input": "atcoder beginner contest", "output": "ABC\n    \n\nThe initial letters of `atcoder`, `beginner` and `contest` are `a`, `b` and\n`c`. Uppercase and concatenate them to obtain `ABC`.\n\n* * *"}, {"input": "resident register number", "output": "RRN\n    \n\n* * *"}, {"input": "k nearest neighbor", "output": "KNN\n    \n\n* * *"}, {"input": "async layered coding", "output": "ALC"}]