Tabata 29 April 2014 - Trig triangle solver

trig_solver.js

/*
http://www.reddit.com/r/dailyprogrammer/comments/2451r5/4282014_challenge_160_easy_trigonometric_triangle/

Solutions:
C = 90
f(a,b) = (a**2 + b**2)**-2 = c
f(a,c) = (c**2 - a**2)**-2 = b
f(b,c) = (c**2 - b**2)**-2 = a
*/

var pow = Math.pow;
var solvers = [
	function (args) {
		args.C = 90;
		return args;
	},
	function () {
		if (!args.c && args.a && args.b) {
			args.c = pow(pow(args.a, 2) + pow(args.b, 2), 0.5);
		}
		return args;
	},
	function () {
		if (!args.a && args.b && args.c) {
			args.a = pow(pow(args.c, 2) - pow(args.b, 2), 0.5);
		}
		return args;
	},
	function () {
		if (!args.b && args.a && args.c) {
			args.b = pow(pow(args.c, 2) - pow(args.a, 2), 0.5);
		}
		return args;
	},
];

function solve(args) {
	solvers.forEach(function(solver) {
		args = solver(args);
	});
	return args;
}

function get_args(str) {
	str = str.split("\n");
	var args = {},
		lines = +str[0],
		line;
		
	while (lines > 0) {
		line = str[str.length - lines];
		line = line.split('=');
		args[line[0]] = +line[1];
		lines--;
	}
	return args;
}

problem = "2\na=3\nc=5";
var args = get_args(problem);
console.info(args);
args = solve(args);
console.info(args);