diff --git a/pages/index/index.js b/pages/index/index.js
index c1c7e0d..307d89f 100644
--- a/pages/index/index.js
+++ b/pages/index/index.js
@@ -84,7 +84,7 @@ Page({
         }, 1000)
         let length = res.data.length
         if (res.data.length > 1) {
-          let num = Math.round(Math.random()*length);
+          let num = Math.round(Math.random()*length)-1;
           console.log('num',num);
           this.setData({
             startList:res.data[num]