Point Distances with Shared Coordinate https://binarysearch.com/contest/Weekly-Contest-47-FeZJewLaN1?questionsetIndex=2

point-distances.js

class Solution {
    solve(points) {
        const byX = {};
        const byY = {};
        const result = [];
        // points.sort((a,b) => a[0] == b[0] ? a[1] - b[1] : a[0] - b[0]);
        for(let [x, y] of points) {
            byX[x] = byX[x] || [];
            byX[x].push(y);
            byY[y] = byY[y] || [];
            byY[y].push(x);
        }
        for(let key in byX) {
            byX[key].sort((a,b) => a - b);
        }
        for(let key in byY) {
            byY[key].sort((a,b) => a - b);
        }
        this.byX = byX;
        this.byY = byY;
console.log(byX, byY)
        for(let i = 0; i < points.length; i++) {
            let [x, y] = points[i];
            let dX = x;
            let dY = y;
            if(byX[x].length > 1 && byY[y].length == 1) {
                // console.log("should be here")
                // We don't want to match the same point.
                dY = this.findClosestY(x, y)// (byX[x][0] == y) ? byX[x][1] : byX[x][0];
            } else if(byX[x].length == 1 && byY[y].length > 1) {
                dX = this.findClosestX(x, y)// (byY[y][0] == x) ? byY[y][1] : byY[y][0];
            } else { // Then both points are valid.
                let min = Number.MAX_SAFE_INTEGER;
                // Try the point that matches on the X axis.
                dY = this.findClosestY(x, y)//(byX[x][0] == y) ? byX[x][1] : byX[x][0];
                min = Math.min(manhattanDistance(x, dX, y, dY), min);
                // Now try the point that matches on the Y axis.
                dY = y;
                dX = this.findClosestX(x, y);//(byY[y][0] == x) ? byY[y][1] : byY[y][0];
                min = Math.min(manhattanDistance(x, dX, y, dY), min);
                result[i] = min;
                continue;
            }
            // console.log(x,y, dX, dY)
            result[i] = manhattanDistance(x, dX, y, dY);
        }
        return result;
    }

    findClosestX(x, y) {
        let minValue = Number.MAX_SAFE_INTEGER;
        let minDelta = Number.MAX_SAFE_INTEGER;
        let index = binarySearch(this.byY[y], x);
        for(let i = Math.max(index - 1, 0); i < Math.min(index + 1, this.byY[y].length); i++) {
            if(i == index) continue;
            let dX = this.byY[y][i];
            let delta = Math.abs(x - dX);
            if(delta < minDelta) {
                minValue = dX;
                minDelta = delta;
            }
        }
        return minValue;
    }
    
    findClosestY(x, y) {
        let minValue = Number.MAX_SAFE_INTEGER;
        let minDelta = Number.MAX_SAFE_INTEGER;
        let index = binarySearch(this.byX[x], y);
        for(let i = Math.max(index - 1, 0); i < Math.min(index + 1, this.byX[x].length); i++) {
            if(i == index) continue;
            let dY = this.byX[x][i];
            let delta = Math.abs(y - dY);
            if(delta < minDelta) {
                minValue = dY;
                minDelta = delta;
            }
        }
        return minValue;
    }
}

const binarySearch = (target, arr) => {
   return binarySearchRec(target, arr, 0, arr.length - 1);
}

const binarySearchRec = (target, arr, low, high) => {
    if(low > high) return;
    console.log("bs", target, low, high)
    let mid = Math.floor(high - low / 2) + low;
    if(arr[mid] == target) {
        return mid;
    } else if(arr[mid] < target) {
        return binarySearchRec(target, arr, mid + 1, high);
    } else {
        return binarySearchRec(target, arr, low, mid - 1);
    }
}

const manhattanDistance = (x, dX, y, dY) =>
    Math.abs(x - dX) + Math.abs(y - dY);