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题目：

Find the largest palindrome made from the product of two n-digit numbers.

Since the result could be very large, you should return the largest palindrome mod 1337.

Example:

Input: 2Output: 987Explanation: 99 x 91 = 9009, 9009 % 1337 = 987

Note:

The range of n is [1,8].

解释：

class Solution:    def largestPalindrome(self, n):        """        :type n: int        :rtype: int        """        if n==1:            return 9        if n==8:            return 475        high=pow(10,n)-1        low=high//10        for i in range(high,low,-1):            pal= int(str(i)+str(i)[::-1])            j=high            while j*j>=pal:                if pal%j==0:                    return pal%1337                j-=1

c++代码：

#include 
   
    #include 
    
     using namespace std;class Solution {
   public:    int largestPalindrome(int n) {
           if(n==1)            return 9;        int high=pow(10,n)-1;        int low=high/10;        for (int i=high;i>low;i--)        {
               long pal=getPal(i);            int j=high;            while(pal/j<=j)            {
                   if(pal%j==0)                {
                       return pal%1337;                }                                    j--;            }        }            }    long getPal(int n)    {
           string n_reverse=to_string(n);        reverse(n_reverse.begin(),n_reverse.end());        //转换为char*        return atol((to_string(n)+n_reverse).c_str());    }};
    
   

解法2：

总结：

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