Th. Exo 3

exo3.js

'use strict';

let solutions = {};
let bestPathValue = 0;

let crop = (mat, col_start, row_start, col_end, row_end) => {
  col_end = col_end || mat.length;
  row_end = row_end || mat[0].length;
  return mat.slice(col_start, col_end).map(
    row => row.slice(row_start, row_end)
    )
}

class Path {
  constructor(path, acc, left, right){
    this.path = path || 'START';
    this.acc =  acc || null;
    this.left = left || null;
    this.right = right || null;
  }
  
  isLeaf() {
    if (!this.left & !this.right) return true;
    return false;
  }
  
  constructFromMatrix(matrix) {
    this.acc += matrix[0][0];
    let dim_col = matrix.length;
    let dim_row = matrix[0].length;
    
    if (dim_col > 1) {
      this.left = new Path(this.path + ' RIGHT', this.acc)
      this.left.constructFromMatrix(crop(matrix, 1, 0));
    }
    if (dim_row > 1) {
      this.right = new Path(this.path + ' DOWN', this.acc)
      this.right.constructFromMatrix(crop(matrix, 0, 1));
    }
    if (this.isLeaf()){
      this.path += ' STOP';
      if (!solutions[this.acc])
        solutions[this.acc] = [this.path];
      else
        solutions[this.acc].push(this.path);
      bestPathValue = bestPathValue > this.acc ? bestPathValue : this.acc;
    }
  }
}

let items = [[1, 2, 3],[0, 4, 5], [0,6, 2], [1, 2, 3]];

let mouse = new Path('START', 0);
mouse.constructFromMatrix(items);

console.log(solutions[bestPathValue]);