GemStones.cpp

#include<iostream>
#include<string>

using namespace std;

int main()
{
    int T;
    int a[26] = {0};
    bool flag[26] = {false};
    int nCount = 0;
     
    cin >> T;
    cin.ignore();
    
    int curTest = 1;
    while(curTest <= T)
    {
	string in;
	getline(cin,in);

	for(int i = 0; i < in.length();i++)
	{
		int ch = ((int)in[i]) - 97;
		if( ch >= 0 && ch < 26 && flag[ch] == false)	
         {  		a[ch]++;
                    flag[ch] = true;
         }
        
	}
        for(int i = 0; i < 26;i++)
	        flag[i] = false;
   
	
	    curTest++;
    }
    
    for(int i = 0 ; i <= 25;i++)
   	if(a[i] == T)
		nCount++;

    cout<<nCount;
	return 0;
}