Given two numbers represented as strings, return multiplication of the numbers as a string.

Note: The numbers can be arbitrarily large and are non-negative.

 

 大数的乘法问题，运用乘法规则就好了。

1 class Solution { 2 public: 3     string multiply(string num1, string num2) { 4         if(num1=="0" || num2=="0") return "0"; 5         string result; 6         int len1=num1.length(); 7         int len2=num2.length(); 8         int len=len1+len2; 9         int* n1=new int[len1];10         int* n2=new int[len2];11         int* multi=new int[len];12         for(int i=0;i
      
       =0;i--)39         {40             if(multi[i]!=0)41             {42                 first_nozero=i;43                 break;44             }45         }46         for(int i=first_nozero;i>=0;i--)47         {48             result+=char(multi[i]+'0');49         }50         delete []n1;51         delete []n2;52         delete []multi;53         54         return result;55     }56 };