1 package myAtoi8; 2 /* 3  * Implement atoi to convert a string to an integer. 4 Hint: Carefully consider all possible input cases. If you want a challenge, please do not see below and ask yourself what are the possible input cases. 5 Notes: It is intended for this problem to be specified vaguely (ie, no given input specs). You are responsible to gather all the input requirements up front. 6 Update (2015-02-10): 7 The signature of the C++ function had been updated. If you still see your function signature accepts a const char * argument, please click the reload button  to reset your code definition. 8 */ 9 10 public class Solution {11     public static int myAtoi(String str) {12         StringBuilder sb=new StringBuilder();13         int flag=0;14         if(str.length()==0)15             return 0;16         else{17             for(int i=0;i
     
      '9')19                     if(str.charAt(i)=='0'||str.charAt(i)==' ')20                         if (sb.length()==0)21                             continue;22                         else23                             break;24                     else if (str.charAt(i)=='-')25                         if (flag==0){26                             flag=-1;27                             sb.append('0');28                         }29                         else30                             break;31                     else if (str.charAt(i)=='+')32                         if (flag==0){33                             flag=1;34                             sb.append('0');35                         }36                         else37                             break;38                     else39                         break;40                 else41                     sb.append(str.charAt(i));        42                 }        43         }44         if(sb.length()==0)45             return 0;46         else if(sb.length()>12)47             str=sb.substring(sb.length()-12);48         else49             str=sb.toString();50         if (flag==-1)51             str="-"+str;52         long result=Long.parseLong(str);53         System.out.println(result);54         if (result>2147483647)55             return 2147483647;56         else if (result<-2147483648)57             return -2147483648;58         else59             return (int)result;60         61     }62     public static void main(String[] args){63         String str1="";//064         String str2="+";//065         String str3="              +45555";//4555566         String str4="              -45555";//-4555567         String str5="2147483647";//214748364768         String str6="2147483648";//214748364769         String str7="+-2";//070         String str8="-+2";//071         String str9="++2";//072         String str10="-2147483648";//-214748364873         String str11="   - 321";//074         String str12="      -11919730356x";//-214748364875         String str13="1234567890123456789012345678901234567890";//214748364776         System.out.println(myAtoi(str1));77         System.out.println(myAtoi(str2));78         System.out.println(myAtoi(str3));79         System.out.println(myAtoi(str4));80         System.out.println(myAtoi(str5));81         System.out.println(myAtoi(str6));82         System.out.println(myAtoi(str7));83         System.out.println(myAtoi(str8));84         System.out.println(myAtoi(str9));85         System.out.println(myAtoi(str10));86         System.out.println(myAtoi(str11));87         System.out.println(myAtoi(str12));88         System.out.println(myAtoi(str13));89 90 91     }92 }