The macro va_arg is used to extract an argument from the fixed micro argument list and advance the pointer to the next argument.

#include<stdio.h>
int main()
{
    int x=4, y, z;
    y = --x;
    z = x--;
    printf("%d, %d, %d\n", x, y, z);
    return 0;
}

#include<stdio.h>
int main()
{
    int a=100, b=200, c;
    c = (a == 100 || b > 200);
    printf("c=%d\n", c);
    return 0;
}

#include<stdio.h>
int main()
{
    int x=55;
    printf("%d, %d, %d\n", x<=55, x=40, x>=10);
    return 0;
}

#include<stdio.h>

int main()
{
    void fun(char*);
    char a[100];
    a[0] = 'A'; a[1] = 'B';
    a[2] = 'C'; a[3] = 'D';
    fun(&a[0]);
    return 0;
}
void fun(char *a)
{
    a++;
    printf("%c", *a);
    a++;
    printf("%c", *a);
}

#include<stdio.h>

void fun(void *p);
int i;

int main()
{
    void *vptr;
    vptr = &i;
    fun(vptr);
    return 0;
}
void fun(void *p)
{
    int **q;
    q = (int**)&p;
    printf("%d\n", **q);
}

#include<stdio.h>
#include<string.h>

int main()
{
    static char s[] = "Hello!";
    printf("%d\n", *(s+strlen(s)));
    return 0;
}

#include<stdio.h>

int main()
{
    int i=4, j=8;
    printf("%d, %d, %d\n", i|j&j|i, i|j&&j|i, i^j);
    return 0;
}