Create 0097-interleaving-string.go

Author: kkr2

go/0097-interleaving-string.go

@@ -0,0 +1,37 @@
+var cache map[[2]int]bool
+var st1 string
+var st2 string
+var st3 string
+
+func isInterleave(s1 string, s2 string, s3 string) bool {
+	if len(s1)+len(s2) != len(s3) {
+		return false
+	}
+	cache = make(map[[2]int]bool)
+	st1 = s1
+	st2 = s2
+	st3 = s3
+	return dfs(0, 0)
+}
+
+func dfs(i, j int) bool {
+	if i >= len(st1) && j >= len(st2) {
+		return true
+	}
+
+	val, ok := cache[[2]int{i, j}]
+	
+	if ok {
+		return val
+	}
+	
+	if i < len(st1) && st1[i] == st3[i+j] && dfs(i+1, j) {
+		return true
+	}
+	if j < len(st2) && st2[j] == st3[i+j] && dfs(i, j+1) {
+		return true
+	}
+	
+	cache[[2]int{i, j}] = false
+	return false
+}