Point out the error in the program

#include<stdio.h>
int main

Point out the error in the program

#include<stdio.h>
int main()
 {
     int a=10;
     void f();
     a = f();
     printf("%d\n", a);
     return 0;
 }
 void f()
 {
     printf("Hi");
 }

2) Which of the following statements are correct about the program?

#include<stdio.h>
int main()
 {
     printf("%p\n", main());
     return 0;
 }

3) What will be the output of the program?

#include<stdio.h>
int func1(int);
int main()
 {
     int k=35;
     k = func1(k=func1(k=func1(k)));
     printf("k=%d\n", k);
     return 0;
 }
 int func1(int k)
 {
     k++;
     return k;
 }

4) What will be the output of the program?

#include<stdio.h>
int fun(int);
int main()
 {
     float k=3;
     fun(k=fun(fun(k)));
     printf("%f\n", k);
     return 0;
 }
int fun(int i)
 {
     i++;
     return i;
 }

5) What will be the output of the program?

#include<stdio.h>
#include<stdlib.h>
int main()
 {
     int i=0;
     i++;
     if(i<=5)
     {
         printf("Study2Online");
         exit(1);
         main();
     }
     return 0;
 }