export type Matrix = number[][];
export type Vector = number[];

/** 完全pivot選択のGauss-Jordan法で複数の連立方程式の解と逆行列を求める
 *
 * @param a 連立方程式の係数
 * @param bs 求めたい連立方程式の右辺
 * @return 連立方程式の解とaの逆行列
export const pivotGaussJordan = (a: Matrix, ...bs: Vector[]): [Matrix, ...Vector[]] => {
  // 次元チェック
  const n = a.length;
  if (!a.every((row) => row.length === n)) throw Error(`a must be a square matrix`);
  const m = bs.length;
  if (!b.every((column) => column.length === n)) throw Error(`b must be the same column length as a`);
  
  /** pivot選択記録用 */
  const indxc: number[] = [];
  /** pivot選択記録用 */
  const indxr: number[] = [];
  /** pivot選択記録用 */
  const ipiv: number[] = new Array(n).fill(0);
 let big = 0;
  for (let i = 0; i < n; i++) {
    big = 0;
    for (let j = 0; j < n; j++) {
      if (ipiv[j] === 1) continue;
      for (let k = 0; k < n; k++) {
  
  
}