var input = '';
var readable = process.stdin;
readable.resume();
readable.setEncoding( 'utf-8' );
readable.on( 'data', function( chunk ) {
  input += chunk;
});

readable.on( 'end', function() {
  var size = 'z'.charCodeAt(0)-'a'.charCodeAt(0);
  var cnt = [];
  for( var i=0; i<=size; i++ ) { cnt.push( 0 ); }
  
  for( var i=0; i<input.length; i++ ) {
    var az = input.toLowerCase().charCodeAt( i )-'a'.charCodeAt(0);
    if( 0 <= az && az <= size ) {
      cnt[ az ]++;
    }
  }
  for( var i=0; i<=size; i++ ) {
    console.log( String.fromCharCode( 'a'.charCodeAt(0)+i ) + " : "+cnt[i] );
  }
});