what is the program output

[sunil17]

#include<stdio.h>
#define PR(a)   printf("%d\t",(int) (a));
#define PRINT(a,b,c) PR(a);PR(b);PR(c);
#define MAX(a,b) (a<b?b:a)
main(){
	int x = 1,y = 2;
		PRINT(MAX(x++,y),x,y);
			PRINT(MAX(x++,y),x,y);
			}

in the output
first itis printing 2 2 2 it's ok
but in the second 3 4 2 is printing
why it is printing 4 .increment is done only one time after fitst printf

[sean]

x is incremented after the first PRINT(), and is incremented after the first parameter to the second PRINT() is evaluated.