Largest Number


Given a list of non negative integers, arrange them such that they form the largest number.

For example, given ​​[3, 30, 34, 5, 9]​​, the largest formed number is ​​9534330​​.

Note: The result may be very large, so you need to return a string instead of an integer.

Credits:
Special thanks to ​​​@ts​​ for adding this problem and creating all test cases.

class Solution {
public:
    //cmp 要声明为静态函数
    static bool cmp(int a,int b)
    {
        char str1[15],str2[15];
        sprintf(str1,"%d",a);
        sprintf(str2,"%d",b);
        string aa,bb;
        aa+=str1;aa+=str2;
        bb+=str2;bb+=str1;
        return aa>bb;
    }
    
    string largestNumber(vector<int>& nums) {
        
        string ans;
        int n=nums.size();
        int i;
        
        sort(nums.begin(),nums.end(),cmp);
        for(i=0;i<n;i++)
        {
            char str[15];
            sprintf(str,"%d",nums[i]);
            ans+=str;
        }
        i=0;
        while(ans[i]=='0'&&i<n)
            i++;
        if(i==n)
            return "0";
        return ans.substr(i);
    }
    
  
};