add new solutions

solutions/30/q3070/solution.go

@@ -0,0 +1,28 @@
+// Package q3070 implements a solution for https://leetcode.com/problems/count-submatrices-with-top-left-element-and-sum-less-than-k/
+package q3070
+
+func countSubmatrices(grid [][]int, k int) int {
+	cnt := 0
+	for r := range grid {
+		for c := 1; c < len(grid[0]); c++ {
+			grid[r][c] += grid[r][c-1]
+		}
+	}
+
+	for r := range grid {
+		for c := range grid[0] {
+			if r > 0 {
+				grid[r][c] += grid[r-1][c]
+			}
+
+			if grid[r][c] <= k {
+				cnt++
+			} else {
+				break
+			}
+		}
+	}
+	return cnt
+}
+
+var _ = countSubmatrices