#include<iostream>
#include<string.h>
using namespace std;
const int n=1e7+9;
char s[n];
int main (){
cin>> s;
int len = strlen(s);
int frequency[26];
for (int i=0; i<26; i++){
frequency[i]= 0;
}
for (int i=0; i<len; i++){
int chr_rank = s[i]-'a';
frequency[chr_rank]++;
}
for (char ch= 'a'; ch<='z'; ch++){
int chr_rank = ch - 'a';
if (frequency[chr_rank]>0){
cout << ch << ':' << frequency [chr_rank] << endl;
}
}
return 0;
}
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