[C puzzle book] Preprocessor for C

#include <stdio.h>
#define FUDGE(k) k+3.14159
#define PR(a) printf("a= %d\t",(int)(a))
#define PRINT(a) PR(a); putchar('\n')
#define PRINT2(a,b) PR(a); PRINT(b)
#define PRINT3(a,b,c) PR(a); PRINT2(b,c)
#define MAX(a,b) (a<b?b:a)


int main(void)
{
    { 
        int x=2;
        PRINT(x*FUDGE(2));
    }

    {
        int ce1;
        for(ce1=0;ce1<=100; ce1+=50)
            PRINT2(ce1, 9./5*ce1+32);
    }

    {
        int x=1 ,y =2;
        PRINT3(MAX(x++,y),x,y);
        PRINT3(MAX(x++,y),x,y);
    }
}

#include <stdio.h>
#define NEG(a)-a
#define weeks(mins) (days(mins)/7)
#define days(mins) (hours(mins)/24)
#define hours(mins) (mins/60)
#define mins(secs) (secs/60)
#define TAB(c,i,oi,t) if(c=='\t')\
        for(t=8-(i-oi-1)%8,oi=i; t; t--)\
        putchar(' ')
#define PR(a) printf(#a"=%d\t",(int)(a))
#define PRINT(a) PR(a); putchar('\n')


int main(void)
{
    {
        int x=1;
        PRINT( -NEG(x) );
    }

    {
        PRINT(weeks(10080));
        PRINT(days(mins(86400)));
    }

    {
        static char input[]="\twihch\tif?";
        char c;
        int i, oldi, temp;

        for(oldi=-1,i=0; (c=input[i])!='\0'; i++)
            if (c<' ')
                       TAB(c,i,oldi,temp);
            else 
                putchar(c);
            putchar('\n');
    }
}