Sort Colors

https://leetcode.com/problems/sort-colors/

计数排序问题

class Solution {
public:
    void sortColors(vector<int>& nums) {
        int rates[3]={0};
        int size=nums.size();
        for(int i=0;i<size;i++)
            rates[nums[i]]++;
        for(int i=0;i<size;i++)
        {
            if(rates[0]!=0)
            {
                nums[i]=0;
                rates[0]--;
            }
            else if(rates[1]!=0)
            {
                nums[i]=1;
                rates[1]--;
            }
            else
            {
                nums[i]=2;
                rates[2]--;
            }
        }
    }
};