import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main {

	public static void main(String[] args) {
		// TODO ?????????????????????????????????????????????

		BufferedReader insBR = new BufferedReader(new InputStreamReader(System.in));
		//??£??????????????????????????????????????°
		String strLine = "";

		while(true){
			try{

				String strScan = insBR.readLine();
				if("".equals(strScan) || strScan == null){
					break;
				}else{
					strLine += strScan;
				}


			}catch(IOException e){
				System.out.println(e);
			}

		}

		//?°????????????????
		strLine = strLine.toLowerCase();
		//System.out.println("strLine:" + strLine);

		//str???????§£??????char[]???????´?
		char[] aryLine= strLine.toCharArray();
		//System.out.println("aryLine.length:" + aryLine.length);

		char x = 'a';

		//int[] intCount = new int[26];

		//a???z?????§?????°?????????
		for(int i = 'a'; i <= 'z'; i++){
			//??¢????????????????????????????????????????????°
			int intCount = 0;
			//????????????length?????°?????????
			for(int j = 0; j < aryLine.length; j++){

				//System.out.println("int i:" + i );

				int alphNum = aryLine[j];
				//System.out.println("alphNum:" + alphNum);
				//??¢???????????????????????????????????¢??????
				if( i == alphNum){
					//System.out.print("i:" + i + "/j:" + alphNum);
					//System.out.print(" ");
					intCount++;
				}
			}

			System.out.print(x++);
			System.out.println(" : " + intCount);

		}
	}

}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz