What will be the output of the program?

#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;
}

char *p;
p = (char*) malloc(100);

#include<stdio.h>

int main()
{
    int arr[]={2, 3, 4, 1, 6};
    printf("%u, %u, %u\n", arr, &arr[0], &arr);
    return 0;
}

#include<stdio.h>

int main()
{
    union a
    {
        int i;
        char ch[2];
    };
    union a u;
    u.ch[0]=3;
    u.ch[1]=2;
    printf("%d, %d, %d\n", u.ch[0], u.ch[1], u.i);
    return 0;
}

#include<stdio.h>

int main()
{
    enum value{VAL1=0, VAL2, VAL3, VAL4, VAL5} var;
    printf("%d\n", sizeof(var));
    return 0;
}

#include<stdio.h>

int main()
{
    struct byte
    {
        int one:1;
    };
    struct byte var = {1};
    printf("%d\n", var.one);
    return 0;
}

#include<stdio.h>

int main()
{
    struct bits
    {
        float f:2;
    }bit;

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

#include<stdio.h>

int main()
{
    struct emp
    {
        char n[20];
        int age;
    };
    struct emp e1 = {"Dravid", 23};
    struct emp e2 = e1;
    if(e1 == e2)
        printf("The structure are equal");
    return 0;
}

#include<stdio.h>
#include<malloc.h>

struct emp
{
    int len;
    char name[1];
};
int main()
{
    char newname[] = "Rahul";
    struct emp *p = (struct emp *) malloc(sizeof(struct emp) -1 +
                    strlen(newname)+1);

    p->len = strlen(newname);
    strcpy(p -> name, newname);
    printf("%d %s\n", p->len, p->name);
    return 0;
}