diff --git a/script.js b/script.js
index bbe8a29..8839ad4 100644
--- a/script.js
+++ b/script.js
@@ -1,4 +1,50 @@
+var scissors = "scissors";
+var paper = "paper";
+var stone = "stone";
+
+var noTimesPlayerWin = 0;
+var noTimesPlayerLose = 0;
+var noTimesDraw = 0;
+
+var userName = "";
+
+var diceRoll = function () {
+  randomDice = Math.floor(Math.random) * 3;
+  if (randomDice == 0) {
+    return scissors;
+  }
+  if (randomDice == 1) {
+    return paper;
+  }
+  if (randomDice == 2) {
+    return stone;
+  }
+};
+
 var main = function (input) {
-  var myOutputValue = 'hello world';
-  return myOutputValue;
+  if (!userName) {
+    if (!input) {
+      return "please input username";
+    }
+    userName = input;
+    return "thank you," + userName + ".you can start playing sps.";
+  }
+  if (input != scissors && input != paper && input != stone) {
+    return "please input scissors,paper or stone.";
+  }
+
+  var playerObject = input;
+  var computerObject = diceRoll();
+
+  if (playerObject == computerObject) {
+    return "draw";
+  }
+  if (
+    (playerObject == scissors && computerObject == paper) ||
+    (playerObject == paper && computerObject == stone) ||
+    (playerObject == stone && computerObject == scissors)
+  ) {
+    return "win";
+  }
+  return "lose";
 };