From 8ea9371421439a774d28d42bae8e406ce981a9c0 Mon Sep 17 00:00:00 2001
From: Hidemichi Shimura <hidemichi.shimura@gmail.com>
Date: Sat, 7 Jan 2023 17:17:20 -0800
Subject: [PATCH 1/2] solve 1427. Perform String Shifts

---
 1427.perform-string-shifts.js | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)
 create mode 100644 1427.perform-string-shifts.js

diff --git a/1427.perform-string-shifts.js b/1427.perform-string-shifts.js
new file mode 100644
index 00000000..a6c81681
--- /dev/null
+++ b/1427.perform-string-shifts.js
@@ -0,0 +1,30 @@
+/* URL of this problem
+ * https://leetcode.com/problems/perform-string-shifts/description/
+ *
+ * @param {string} s
+ * @param {number[][]} shift
+ * @return {string}
+ */
+
+var stringShift = function(s, shift) {
+    const Shifted = [...s];
+    
+    for (let i = 0; i < shift.length; i++) {
+        const ShiftAmount = shift[i][1];
+
+        // 0 means left shift and 1 for right shift for shift[1][0]
+        if (shift[i][0] === 0) {
+            for (let j = 0; j < ShiftAmount; j++) {
+                Shifted.push(Shifted.shift());
+            }
+        } else {
+            for (let j = 0; j < ShiftAmount; j++) {
+                Shifted.unshift(Shifted.pop());
+            }
+        }
+    }
+
+    return Shifted.join("");
+};
+
+module.exports = stringShift;
\ No newline at end of file

From 36e95c37ffb19c50c72c609735cc7bd82f1e0db3 Mon Sep 17 00:00:00 2001
From: Hidemichi Shimura <hidemichi.shimura@gmail.com>
Date: Sat, 7 Jan 2023 17:17:39 -0800
Subject: [PATCH 2/2] test function stringShift

---
 stringShift.test.js | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)
 create mode 100644 stringShift.test.js

diff --git a/stringShift.test.js b/stringShift.test.js
new file mode 100644
index 00000000..0fe250ce
--- /dev/null
+++ b/stringShift.test.js
@@ -0,0 +1,17 @@
+const stringShift = require("./1427.perform-string-shifts");
+
+test("Return the final string after the shift operations", () => {
+    expect(stringShift("abcdefg", [[1,1],[1,1],[0,2],[1,3]])).toBe("efgabcd");
+});
+
+test("Return an empty string if the input string is empty", () => {
+    expect(stringShift("", [[1,1],[1,1],[0,2],[1,3]])).toBe("");
+});
+
+test("Return the original string if the input shift has no element", () => {
+    expect(stringShift("abcdefg", [])).toBe("abcdefg");
+});
+
+test("Return the original string if all of the shift amounts are 0", () => {
+    expect(stringShift("abcdefg", [[1,0],[0,0],[0,0],[1,0]])).toBe("abcdefg");
+});
\ No newline at end of file