leetcode-next permutation

EdgeCase太容易出错。有两处都是应该为<=但写成了<。

#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

class Solution2 {
public:
    void nextPermutation(vector<int> &num) {
        int last = num.size() - 1;
    }
};
class Solution {
public:
    void nextPermutation(vector<int> &num) {
        int last = num.size() - 1;
        int vioIndex = last;
        while (vioIndex - 1 >= 0 && num[vioIndex] <= num[vioIndex - 1])//出错点！是<=不是<！[1,1]
        {
            vioIndex--;
        }
        if (vioIndex != 0)
        {//存在vioIndex
            vioIndex--;
            int rightIndex = last;
            while (num[rightIndex] <=num[vioIndex])//出错点。是<=,不是< [1,5,1]
                rightIndex--;
            //swap vio and rightIndex
            int temp = num[vioIndex];
            num[vioIndex] = num[rightIndex];
            num[rightIndex] = temp;
            //reverse from vioIndex+1 to the end
            vioIndex++;
        }

        //不存在vioIndex.直接逆序就行了
        int beg = vioIndex;
        int end = last;
        while (beg < end)
        {
            int temp = num[end];
            num[end] = num[beg];
            num[beg] = temp;
            beg++; end--;
        }

        //next_permutation(num.begin(), num.end());
        printV(num);
    }
    void printV(vector<int> &num)
    {
        for (int i = 0; i < num.size(); i++)
        {
            //cout << (i == 0 ? num[i] : ',' << num[i]);
            if (i == 0)
                cout << num[i];
            else
                cout << ',' << num[i];
        }
        cout << endl;
    }
};
int main()
{
    Solution s;
    int a[] = { 1,  1 };
    vector<int> v(a, a + 2);
    s.nextPermutation(v);
    return 0;
}

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http://fisherlei.blogspot.com/2012/12/leetcode-next-permutation.html