function Main(input) {
    var array = input.replace(/\r?\n+$/, '').split(/\s+/).map(Number);
    var count = 0;
    for(var i = 0; i < array.length; i++) {
        for(var j = i + 1; j < array.length; j++) {
            if (array[i] == array[j]) { count++ }
        }
    }

    console.log(array.length - count);
}

var character = "";
process.stdin.on('data', function(char){ character += char });
process.stdin.on('end', function(){ Main(character); });
process.on('SIGINT', function() { Main(character); process.exit(0); });