upd: Longest Common Prefix

Author: bt404

README.md

@@ -19,3 +19,4 @@ LeetCode JavaScript Solution
 | Remove Nth Node From End of List | Medium | 2018-03-16 |
 | Valid Parentheses | Easy | 2018-03-16 |
 | Remove Duplicates from Sorted Array | Easy | 2018-03-16 |
+| Longest Common Prefix | Easy | 2018-03-16 |

src/longestCommonPrefix.js

@@ -0,0 +1,22 @@
+/**
+ * @param {string[]} strs
+ * @return {string}
+ */
+var longestCommonPrefix = function(strs) {
+  if (!strs.length) return '';
+  let i = 0;
+  let ret = '';
+  while (true) {
+    let temp = strs[0] && strs[0][i] || '';
+    let flag = strs.reduce((prev, cur) => {
+      return prev && cur[i] === temp;
+    }, true);
+    if (flag) {
+      ++i;
+      ret += temp;
+    } else {
+      break;
+    }
+  }
+  return ret;
+};