import std.algorithm, std.array, std.container, std.range, std.bitmanip; import std.numeric, std.math, std.bigint, std.random, core.bitop; import std.string, std.regex, std.conv, std.stdio, std.typecons; void main() { auto rd = readln.split.map!(to!real); auto a = rd[0], b = rd[1]; if (a < b) swap(a, b); writefln("%.6f", (a ^^ 2 - b ^^ 2).sqrt); }