function Main (input) {
	var args = input.split('\n');
	var n = args[0];
	var m = args[1];

	var per_k = parseInt(parseInt(n / m) / 1000);
	var res = per_k * 1000;
	console.log(res);
}

// Don't edit this line!
Main(require("fs").readFileSync("/dev/stdin", "utf8"));