Method swap

NextPermutation.java:17–22

(int nums[],int i,int j)

    }
    
    public static void swap(int nums[],int i,int j)
    {
        int temp=nums[i];
        nums[i]=nums[j];
        nums[j]=temp;
    }
    
    public static void reverse(int nums[],int i,int j)
    {