Create 1092-shortest-common-supersequence.js

Author: everthis

1092-shortest-common-supersequence.js

@@ -0,0 +1,32 @@
+/**
+ * @param {string} str1
+ * @param {string} str2
+ * @return {string}
+ */
+const shortestCommonSupersequence = function(str1, str2) {
+  const len1 = str1.length
+  const len2 = str2.length
+  const mat = Array.from({ length: len1 + 1 }, () =>
+    new Array(len2 + 1).fill(0)
+  )
+  for (let i = 0; i <= len1; i++) {
+    for (let j = 0; j <= len2; j++) {
+      if (i == 0) {
+        mat[i][j] = str2.slice(0, j)
+        continue
+      }
+      if (j == 0) {
+        mat[i][j] = str1.slice(0, i)
+        continue
+      }
+      mat[i][j] = mat[i - 1][j] + str1[i - 1]
+      let cand1 = mat[i][j - 1] + str2[j - 1]
+      if (cand1.length < mat[i][j].length) mat[i][j] = cand1
+      if (str1[i - 1] === str2[j - 1]) {
+        let cand2 = mat[i - 1][j - 1] + str1[i - 1]
+        if (cand2.length < mat[i][j].length) mat[i][j] = cand2
+      }
+    }
+  }
+  return mat[len1][len2]
+}