vinary-search-1337.js

/**
 * @param {number[][]} mat
 * @param {number} k
 * @return {number[]}
 */
var kWeakestRows = function(mat, k) {
    const n = mat.length;
    let outArr = [];
    for(let i=0; i<n; i++) {
        outArr.push({count: 0, index: i})
        
        const m = mat[i].length;
        let s = 0;
        let e = m-1;
        
        // Using Binary search
        while(s <= e) {
            let mid = Math.floor(s + (e-s)/2);
            
            if(mat[i][mid] === 1 && (mid === m-1 || mat[i][mid+1] === 0)) {
                outArr[i]['count'] = mid+1;
                break;
            }
            if(mat[i][mid] === 0) {
                e = mid - 1;
            } else if(mat[i][mid] === 1) {
                s = mid + 1;
            }   
        }
    }
    
    outArr.sort((a,b) => a.count - b.count);
    
    let finalArr = [];
    for(let i=0; i<k; i++) {
        finalArr.push(outArr[i].index);
    }
    
    return finalArr;
};