next permutation

//Implement next permutation, which rearranges numbers into the lexicographically next greater permutation of numbers.
//
//If such arrangement is not possible, it must rearrange it as the lowest possible order (ie, sorted in ascending order).
//
//The replacement must be in-place, do not allocate extra memory.
//
//Here are some examples. Inputs are in the left-hand column and its corresponding outputs are in the right-hand column.
//1,2,3 → 1,3,2
//3,2,1 → 1,2,3
//1,1,5 → 1,5,1
public class NextPermutation {


public static void main(String[] args) {
// TODO 自动生成的方法存根


}
public void nextPermutation(int[] num) {
if(num.length==0||num.length==1){
return;
}

int i=num.length-2;
//=要注意
while(i>=0&&num[i]>=num[i+1])
    i--;
int k=num.length-1;
        if(i>=0){
        int min=i+1;
        for(int j=i+2;j         //要后面的
        if(num[j]>num[i]&&num[min]>=num[j]){
        min=j;
        }
        }
        int temp=num[i];
        num[i]=num[min];
        num[min]=temp;
       
        for(i=i+1;i         int temp1=num[k];
        num[k]=num[i];
        num[i]=temp1;
        }
        return;
        }
        //换位置
        for(i=0;i     int temp1=num[k];
    num[k]=num[i];
    num[i]=temp1;
    }
        return;
        
        
       
    }


}