LeetCode（179） Largest Number

Posted 2022-06-22 逆風的薔薇

题目

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.

分析

把给定的整数数组，排成一个值最大的字符串。 一个很常见的问题，转换为字符串数组排序。

代码

/*179. Largest Number*/

#include <iostream>
#include <string>
#include <vector>
#include <algorithm>

using namespace std;

bool cmp(string &s1, string &s2)

	string a = s1 + s2, b = s2 + s1;
	return a > b;


class Solution 
public:
	string largestNumber(vector<int>& nums) 
		if (nums.empty())
			return "";

		vector<string> vs;
		int n = nums.size();

		for (int i = 0; i < n; ++i)
		
			char tmp[10];
			snprintf(tmp, 10, "%d", nums[i]);

			vs.push_back(tmp);
		//for

		sort(vs.begin(), vs.end(),cmp);

		string ret;
		for (int i = 0; i < n; ++i)
			ret += vs[i];
		int idx = 0,len = ret.size();
		while (idx < len - 1 && ret[idx] == '0')
			++idx;

		return ret.substr(idx);
	
;

int main()

	vector<int> v =  0,0 ;

	cout << Solution().largestNumber(v) << endl;

	system("pause");
	return 0;