Biased Random Walk

function biasedrandomwalkPathfind(grid, start, end, allowDiag, hFn) {
  const h = hFn || HEURISTICS.manhattan;
  const prev = new Map();
  let r = start[0];
  let c = start[1];
  for (let step = 0; step < grid.length * grid[0].length * 2; step++) {
    visitNode(r, c);
    if (r === end[0] && c === end[1]) {
      reconstructPath(prev, start, end);
      return;
    }
    const neighbors = getNeighbors(grid, r, c, allowDiag);
    if (!neighbors.length) break;
    sortByHeuristic(neighbors, h, end[0], end[1]);
    const pick = neighbors[Math.random() < 0.7 ? 0 : Math.floor(Math.random() * neighbors.length)];
    const pk = key(pick[0], pick[1]);
    if (!prev.has(pk) && !(pick[0] === start[0] && pick[1] === start[1])) prev.set(pk, [r, c]);
    r = pick[0];
    c = pick[1];
    pushFrontier(r, c);
  }
  reportNoPath();
}

def biasedrandomwalkPathfind(grid, start, end, allowDiag, hFn):
    h = (hFn or HEURISTICS.manhattan)
    prev = Map()
    r = start[0]
    c = start[1]
    for step in range(((grid.length * grid[0].length) * 2)):
        visitNode(r, c)
        if ((r == end[0]) and (c == end[1])):
            reconstructPath(prev, start, end)
            return
        neighbors = getNeighbors(grid, r, c, allowDiag)
        if not neighbors.length:
            break
        sortByHeuristic(neighbors, h, end[0], end[1])
        pick = neighbors[(0 if (random() < 0.7) else int((random() * neighbors.length)))]
        pk = key(pick[0], pick[1])
        if (not prev.has(pk) and not ((pick[0] == start[0]) and (pick[1] == start[1]))):
            prev.set(pk, [r, c])
        r = pick[0]
        c = pick[1]
        pushFrontier(r, c)
    reportNoPath()

#include <vector>
#include <algorithm>
#include <cmath>
void biasedrandomwalkPathfind(int grid, int start, int end, int allowDiag, int hFn) {
    auto h = (hFn || HEURISTICS.manhattan);
    auto prev = Map();
    auto r = start[0];
    auto c = start[1];
    for(int step=0; step<((grid.length * grid[0].length) * 2); step++) {
        visitNode(r, c);
        if(((r == end[0]) && (c == end[1]))) {
            reconstructPath(prev, start, end);
            return;
        }
        auto neighbors = getNeighbors(grid, r, c, allowDiag);
        if(!neighbors.length) {
            break;
        }
        sortByHeuristic(neighbors, h, end[0], end[1]);
        auto pick = neighbors[(((std::random() < 0.7)) ? (0) : ((int)std::floor((std::random() * neighbors.length))))];
        auto pk = key(pick[0], pick[1]);
        if((!prev.has(pk) && !((pick[0] == start[0]) && (pick[1] == start[1])))) {
            prev.set(pk, [r, c]);
        }
        r = pick[0];
        c = pick[1];
        pushFrontier(r, c);
    }
    reportNoPath();
}

public void biasedrandomwalkPathfind(int grid, int start, int end, int allowDiag, int hFn) {
    var h = (hFn || HEURISTICS.manhattan);
    var prev = Map();
    var r = start[0];
    var c = start[1];
    for(int step=0; step<((grid.length * grid[0].length) * 2); step++) {
        visitNode(r, c);
        if(((r == end[0]) && (c == end[1]))) {
            reconstructPath(prev, start, end);
            return;
        }
        var neighbors = getNeighbors(grid, r, c, allowDiag);
        if(!neighbors.length) {
            break;
        }
        sortByHeuristic(neighbors, h, end[0], end[1]);
        var pick = neighbors[(((random() < 0.7)) ? (0) : ((int)Math.Floor((double)(random() * neighbors.length))))];
        var pk = key(pick[0], pick[1]);
        if((!prev.has(pk) && !((pick[0] == start[0]) && (pick[1] == start[1])))) {
            prev.set(pk, [r, c]);
        }
        r = pick[0];
        c = pick[1];
        pushFrontier(r, c);
    }
    reportNoPath();
}

#include <stdio.h>
#include <math.h>
void biasedrandomwalkPathfind(int grid, int start, int end, int allowDiag, int hFn) {
    var h = (hFn || HEURISTICS.manhattan);
    var prev = Map();
    var r = start[0];
    var c = start[1];
    for(int step=0; step<((grid.length * grid[0].length) * 2); step++) {
        visitNode(r, c);
        if(((r == end[0]) && (c == end[1]))) {
            reconstructPath(prev, start, end);
            return;
        }
        var neighbors = getNeighbors(grid, r, c, allowDiag);
        if(!neighbors.length) {
            break;
        }
        sortByHeuristic(neighbors, h, end[0], end[1]);
        var pick = neighbors[(((random() < 0.7)) ? (0) : ((int)floor((random() * neighbors.length))))];
        var pk = key(pick[0], pick[1]);
        if((!prev.has(pk) && !((pick[0] == start[0]) && (pick[1] == start[1])))) {
            prev.set(pk, [r, c]);
        }
        r = pick[0];
        c = pick[1];
        pushFrontier(r, c);
    }
    reportNoPath();
}