import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		
		//??\??????????????????????????????Scanner???????????§???????????????
		Scanner scan = new Scanner(System.in);
		
		//??¢???????????????????????¨???????????????
		int[] count = new int[26];

		//?¬?????????????????????????????????°
		while(scan.hasNext()){
			//?¬?????????????????????????
			String text = scan.next();
			
			//char??????????????????????????\?????????
			char[] cArray = text.toCharArray();
			//??\??£???char?????°?????????
			for(int i = 0; i < cArray.length; i++){
				//??¢???????????????????????????????????§??????
				for(int j = 0; j < 26 ; j++){
					//??§??????????????°
					if(cArray[i] == j + 65){
						count[j]++;
					//?°???????????????°
					} else if (cArray[i] == j + 97){
						count[j]++;
						
					}	
				}
			}
		}
		//??¨???
		for(int i = 0; i < 26; i++){
			System.out.println((char)('a'+ i) + " : " + count[i]);
		}
	}

}
/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