function Main(input) {
		input = input.split(" ");
		const num = parseInt(input[0], 10);

if(num%2!=0 && num%3!=0 &&num%4!=0 && num%5!=0 && num%6!=0 &&num%7!=0 && num%8!=0 && num%9!=0 ){
console.log(num-1);
return;
}

		var min = 0;
		var res = [0, 0];
		for (i = 1; i <= num; i++) {
				if (num % i == 0) {
						if (min == 0 || (i - 1) + (num / i - 1) < min) {
								res = [i, num / i];
								min = res[0] + res[1];
						}
				}
		}
		console.log(res[0] - 1 + res[1] - 1);
}
Main(require("fs").readFileSync("/dev/stdin", "utf8"));