add new solutions

solutions/15/q1594/solution.go

@@ -0,0 +1,35 @@
+// Package q1594 implements a solution for https://leetcode.com/problems/maximum-non-negative-product-in-a-matrix/
+package q1594
+
+const MOD = 1e9 + 7
+
+func maxProductPath(grid [][]int) int {
+	buf := make([][2]int, len(grid[0]))
+
+	buf[0] = [2]int{grid[0][0], grid[0][0]}
+	for c := 1; c < len(grid[0]); c++ {
+		num := grid[0][c]
+		n1, n2 := num*buf[c-1][0], num*buf[c-1][1]
+		buf[c] = [2]int{max(n1, n2), min(n1, n2)}
+	}
+
+	for r := 1; r < len(grid); r++ {
+		num := grid[r][0]
+		n1, n2 := num*buf[0][0], num*buf[0][1]
+		buf[0] = [2]int{max(n1, n2), min(n1, n2)}
+
+		for c := 1; c < len(grid[0]); c++ {
+			num := grid[r][c]
+			n1, n2 := num*buf[c][0], num*buf[c][1]
+			n3, n4 := num*buf[c-1][0], num*buf[c-1][1]
+			buf[c] = [2]int{
+				max(n1, n2, n3, n4),
+				min(n1, n2, n3, n4),
+			}
+		}
+	}
+
+	return max(-1, buf[len(buf)-1][0]%MOD)
+}
+
+var _ = maxProductPath