#define INC(X) X++
void main()
{
   int x=4;
   printf("%d", INC(x++));
}

A.

int xstrlen(char *s)
{
    int length=0;
    while(*s!='\0')
    {    length++; s++; }
    return (length);
}

B.	

int xstrlen(char s)
{
    int length=0;
    while(*s!='\0')
        length++; s++;
    return (length);
}

C.	

int xstrlen(char *s)
{
    int length=0;
    while(*s!='\0')
        length++;
    return (length);
}

D.	

int xstrlen(char *s)
{
    int length=0;
    while(*s!='\0')
        s++;
    return (length);
}

#include<stdio.h>

int main()
{
    int i;
    i = printf("How r u\n");
    i = printf("%d\n", i);
    printf("%d\n", i);
    return 0;
}

#include<stdio.h>
#include<math.h>

int main()
{
    float i = 2.5;
    printf("%f, %d", floor(i), ceil(i));
    return 0;
}

#include<stdio.h>

int main()
{
    int i;
    i = scanf("%d %d", &i, &i);
    printf("%d\n", i);
    return 0;
}

#include<stdio.h>

int main()
{
    int i;
    char c;
    for(i=1; i<=5; i++)
    {
        scanf("%c", &c); /* given input is 'b' */
        ungetc(c, stdout);
        printf("%c", c);
        ungetc(c, stdin);
    }
    return 0;
}