A question regarding switch/case

[LarryChen]

Here is the code,

int main()
{	
	int i=4;
	switch(i)
	 {
	    default:printf("zero\n");
	    case 1: printf("one\n");
		   break;
	    case 2:printf("two\n");
		  break;
		case 3: printf("three\n");
		  break;		
	  }

	return 0;
}

Why does the output result include "one"? Thanks.