Leetcode Note: Go - The K Weakest Rows in a Matrix

// Linear Search, Sort O(M*N + MlogM) ) | O(M)
func kWeakestRows(mat [][]int, k int) []int {
    countRow := make([][]int, 0)
    for rowIdx, row := range(mat){
        count := 0
        for _, num := range(row){
            count += num
        }
        countRow = append(countRow, []int{rowIdx, count})
    }
    
    sort.Slice(countRow, func(i, j int)bool{
        if countRow[i][1] == countRow[j][1]{
            return countRow[i][0] < countRow[j][0]
        }
        return countRow[i][1] < countRow[j][1]
    })
    res := make([]int, k)
    for i:=0; i < k; i++{
        res[i] = countRow[i][0]
    }
    return res
}