add new solutions

solutions/0/q72/solution.go

@@ -0,0 +1,36 @@
+package q72
+
+func make2d[T any](rows, cols int) [][]T {
+	alloc := make([]T, rows*cols)
+	ret := make([][]T, rows)
+	for i := range ret {
+		ret[i] = alloc[cols*i : cols*(i+1)]
+	}
+	return ret
+}
+
+func minDistance(word1 string, word2 string) int {
+	minDists := make2d[int](len(word1)+1, len(word2)+1)
+
+	for i1 := range len(word1) {
+		minDists[i1+1][0] = i1 + 1
+	}
+	for i2 := range len(word2) {
+		minDists[0][i2+1] = i2 + 1
+	}
+
+	for i1 := 1; i1 <= len(word1); i1++ {
+		for i2 := 1; i2 <= len(word2); i2++ {
+			if word1[i1-1] == word2[i2-1] {
+				minDists[i1][i2] = minDists[i1-1][i2-1]
+			} else {
+				minDists[i1][i2] = min(
+					minDists[i1-1][i2], minDists[i1][i2-1], minDists[i1-1][i2-1],
+				) + 1
+			}
+		}
+	}
+	return minDists[len(word1)][len(word2)]
+}
+
+var _ = minDistance