What will be the output of the program?

#include<stdio.h>
int main()
{
    int X=40;
    {
        int X=20;
        printf("%d ", X);
    }
    printf("%d\n", X);
    return 0;
}

#include<stdio.h>
#define MIN(x, y) (x<y)? x : y;
int main()
{
    int x=3, y=4, z;
    z = MIN(x+y/2, y-1);
    if(z > 0)
        printf("%d\n", z);
    return 0;
}

FILE *fp;
fp = fopen("source.txt", "rb");

#include<stdio.h>
#include<stdlib.h>

union employee
{
    char name[15];
    int age;
    float salary;
};
const union employee e1;

int main()
{
    strcpy(e1.name, "K");
    printf("%s %d %f", e1.name, e1.age, e1.salary);
    return 0;
}

#include<stdio.h>

int main()
{
    struct bits
    {
        int i:40;
    }bit;

    printf("%d\n", sizeof(bit));
    return 0;
}

#include<stdio.h>
#include<stdarg.h>

int main()
{
    void display(int num, ...);
    display(4, 12.5, 13.5, 14.5, 44.3);
    return 0;
}
void display(int num, ...)
{
    float c; int j;
    va_list ptr;
    va_start(ptr, num);
    for(j=1; j<=num; j++)
    {
        c = va_arg(ptr, float);
        printf("%f", c);
    }
}

/* sample.c */
#include<stdio.h>

int main(int argc, char *argv[])
{
    int j;
    j = argv[1] + argv[2] + argv[3];
    printf("%d", j);
    return 0;
}