Time: 102 ms (58.50%), Space: 44.8 MB (65.08%) - LeetHub

Author: nhemnt

97-interleaving-string/97-interleaving-string.js

@@ -0,0 +1,30 @@
+/**
+ * @param {string} s1
+ * @param {string} s2
+ * @param {string} s3
+ * @return {boolean}
+ */
+
+var isInterleave = function(s1, s2, s3) {
+  const l1 = s1.length, l2 = s2.length, l3= s3.length;
+  if(l3 !== l2 + l1) return false;
+  let m = new Map();
+  const check = (p1,p2,p3) => {
+    if(l1 === p1) return s2.slice(p2) === s3.slice(p3);
+    if(l2 === p2) return s1.slice(p1) === s3.slice(p3);
+    const k = `${p1}-${p2}`
+    if(m.has(k)) {
+      return m.get(k);
+    }
+    let res = false;
+    if(s1[p1] === s3[p3] && s2[p2] === s3[p3]) res = check(p1+1, p2, p3+1) || check(p1, p2+1, p3+1);
+    else if(s1[p1] === s3[p3]) res = check(p1+1, p2, p3+1);
+    else if(s2[p2] === s3[p3]) res = check(p1, p2+1, p3+1);
+    m.set(k, res);
+    return res;
+  }
+  
+
+  return check(0,0,0);
+   
+};