From 81a20a3e93a6c14c0077bf34940cea8e60a2ab04 Mon Sep 17 00:00:00 2001
From: Tanya Chauhan <tanya9@uber.com>
Date: Fri, 14 Aug 2020 00:58:11 +0530
Subject: [PATCH] Added the algorithm for atoi()

---
 atoi.cpp | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 50 insertions(+)
 create mode 100644 atoi.cpp

diff --git a/atoi.cpp b/atoi.cpp
new file mode 100644
index 0000000..b88c6c4
--- /dev/null
+++ b/atoi.cpp
@@ -0,0 +1,50 @@
+#include <iostream>
+using namespace std;
+int myAtoi(string str) {
+        int n=str.size();
+        int i=0;
+        while(i<n && str[i]==' '){
+            i++;
+        }
+        if(i==n){
+            return 0;
+        }
+        int sign=1;
+        if(str[i]=='-'){
+            sign=-1;
+            i++;
+        }
+        else if(str[i]=='+'){
+            i++;
+        }
+        if(i==n || !(str[i]>='0' && str[i]<='9')){
+            return 0;
+        }
+        long long ans=0;
+        for(i;i<n;i++){
+            if(str[i]>='0' && str[i]<='9'){
+                if(sign==1){
+                    if(INT_MAX/10<ans){
+                        return INT_MAX;
+                    }
+                    if(INT_MAX/10==ans && str[i]>'7'){
+                        return INT_MAX;
+                    }
+                }
+                if(sign==-1){
+                    if(INT_MAX/10<ans){
+                        return INT_MIN;
+                    }
+                    if(INT_MAX/10==ans && str[i]>'8'){
+                        return INT_MIN;
+                    }
+                }
+                ans*=10;
+                ans+=str[i]-'0';
+            }
+            else{
+                break;
+            }
+        }
+        return sign*ans;
+    }
\ No newline at end of file