From e7f861c77df0947b6eee758f1b7b974f1a076138 Mon Sep 17 00:00:00 2001
From: Pin Lin <moneycat711@gmail.com>
Date: Wed, 6 May 2020 06:24:51 +0800
Subject: [PATCH] =?UTF-8?q?=E5=AF=A6=E4=BD=9C=E6=8C=89=E4=B8=8B=200=20?=
 =?UTF-8?q?=E5=BE=8C=E6=80=8E=E9=BA=BC=E8=99=95=E7=90=86?=
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---
 AndroidCalculator/Calculator.swift | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/AndroidCalculator/Calculator.swift b/AndroidCalculator/Calculator.swift
index 41a0982..a9c6f6b 100644
--- a/AndroidCalculator/Calculator.swift
+++ b/AndroidCalculator/Calculator.swift
@@ -27,6 +27,16 @@ class Calculator {
     case "AC":
       // 清空到剩下 0
       formula = ["0"]
+      
+    case "0":
+      if formula.last == "0" {
+        return
+      } else if ["+", "-", "×", "÷"].firstIndex(of: formula.last!) != nil {
+        formula.append(text)
+      } else {
+        formula.append(formula.popLast()! + text)
+      }
+      
     default:
       formula.append(text)
     }