Give the output on the screen of the following program

#include <stdio.h>

#define PRINT(format,x) printf(#x " = %"#format"\t",x)
#define NL putchar('\n');


#define PRINT1(f,x) PRINT(f,x);NL
#define PRINT2(f,x1,x2) PRINT(f,x1);PRINT1(f,x2)
#define PRINT3(f,x1,x2,x3) PRINT(f,x1);PRINT2(f,x2,x3)
#define PRINT4(f,x1,x2,x3,x4) PRINT(f,x1);PRINT3(f,x2,x3,x4)

int main()
{
     int x , y, z;

     x=y=0;
     while(y<10) ++y; x+=y;
     PRINT2(d,x,y);

     x=y=0;
     while(y<10) x+= ++y;
     PRINT2(d,x,y);

     y=1;
     while(y<10){
          x=y++;z=++y;
     }
     PRINT3(d,x,y,z);

     for(y=1;y<10;y++) x=y;
     PRINT2(d,x,y);

     for(y=1;(x=y)<10;y++);
     PRINT2(d,x,y);

     for(x=0,y=1000;y>1;x++,y/=10)
     PRINT2(d,x,y);

     for(x=0,y=1000;y>1;x++,y/=10) {
          PRINT2(d,x,y);}

     return 0;
}


Difficulty level
This exercise is mostly suitable for students
x = 10	y = 10	
x = 55	y = 10	
x = 9	y = 11	z = 11	
x = 9	y = 10	
x = 10	y = 10	
x = 0	x = 1	x = 2	y = 1	
x = 0	y = 1000	
x = 1	y = 100	
x = 2	y = 10	 

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