'use strict';

const round = Math.round;
const floor = Math.floor;
const abs = Math.abs;
const cos = Math.cos;
const sin = Math.sin;
const tan = Math.tan;
const pow = Math.pow;
const pi = Math.PI;

let cl = (...a) => console.log(...a);

Array.prototype.copy = function () {
    let res = new Array();
    for (let i of this) {
        if (Array.isArray(i)) {
            res.push(i.copy());
        } else {
            res.push(i);
        }
    }
    return res;
};

Number.prototype.toFixed = function (n = 3) {
    let s = this.toString();
    let index = s.indexOf('.');
    if (index === -1) {
        return this;
    }
    return parseFloat(s.slice(0, index + n));
};

var ina, inb, sol;

function init() {
	ina = $('#a-input');
	inb = $('#b-input');
	sol = $('#sol');
}

function getIn() {
	let A = ina.val().split('\n').map(e => e.split(' ').map(c => parseFloat(c)));
	let B = inb.val().split('\n').map(e => parseFloat(e));
	return {a:A, b:B};
}

function solve() {
    let data = getIn();
    const { solution, determinant } = gauss(data.a.copy(), [data.b.copy()]);
    printCheck(data.a, solution[0], data.b, determinant);
    let revA = revMatrix(data.a.copy());
    printRev(revA);
}

function printCheck(A, x, b, det) {
    let t = $('<table></table>');
    t.addClass('ui-table');
    for (let i = 0; i < x.length; i++) {
        let r = $('<tr></tr>');
        r.append($(`<td>X<sub>${i + 1}</sub></td>`));
        r.append($(`<td>${x[i]}</td>`));
        t.append(r);
    }
    let e = $('<div>Решение</div>');
    e.addClass('ui');
    e.append(t);
    let text = $(`<div>Определитель:${det}</div>`);
    text.css('font-size', '80%');
    text.addClass('ui-text');
    e.append(text);
    sol.append(e);
}

function printRev(A) {
    let n = A.length;
    let t = $('<table></table>');
    t.addClass('ui-table');
    for (let i = 0; i < n; i++) {
        let r = $('<tr></tr>');
        for (let j = 0; j < n; j++) {
            let d = $(`<td>${A[i][j].toFixed()}</td>`);
            r.append(d);
        }
        t.append(r);
    }

    let e = $('<div>Обратная матрица</div>');
    e.addClass('ui');
    e.addClass('ui-text');
    e.append(t);
    sol.append(e);

}

function gauss(A, bs) {
	let n = A.length;
	let x = new Array();
	for (let ib = 0; ib < bs.length; ib++) {
		x.push(new Array());
		for (let j = 0; j < n; j++) {
			x[ib].push(0);
		}
	}
	//Прямой ход
	for (let i = 0; i < n; i++) {
		if (A[i][i] === 0) {
			cl(`Элемент [${i}] равен 0`);
			return;
		}
		for (let j = i + 1; j < n; j++) {
			let m = A[i][j] / A[i][i];
			
			for (let k = i; k < n; k++) {
				A[j][k] -= A[i][k] * m;
			}
			
			for (let ib = 0; ib < bs.length; ib++) {
				bs[ib][j] -= bs[ib][i] * m;
			}
		}
    }
	//Обратный ход
	for (let ib = 0; ib < bs.length; ib++) {
		x[ib][n - 1] = bs[ib][n - 1] / A[n - 1][n - 1];
		
		for (let i = n - 2; i >= 0; i--) {
			let m = 0;
			for (let k = i + 1; k < n; k++) {
				m += A[i][k] * x[ib][k];
			}
			x[ib][i] = (bs[ib][i] - m) / A[i][i];
		}
	}

    let d = 1;
    for (let i = 0; i < n; i++) {
        d *= A[i][i];
    }

    return {solution:x, determinant:d};
}

function revMatrix(A) {
    const n = A.length;
    let b = new Array();
    for (let i = 0; i < n; i++) {
        b.push(new Array());
        for (let j = 0; j < n; j++) {
            b[i].push(i === j ? 1 : 0);
        }
    }
    let { solution } = gauss(A.slice(), b.slice());
    for (let i = 0; i < solution.length; i++) {
        for (let j = 0; j < i; j++) {
            let temp = solution[i][j];
            solution[i][j] = solution[j][i];
            solution[j][i] = temp;
        }
    }

    return solution;
}