Program to compare two input strings in C

#include 
#include 
#include 
#include 
 char s1[80],s2[80];
 int a,b;
int strcmp(char *s,char *t);
void main()
{
 int c;
 clrscr();
 printf("Enter string 1 :-  ");
 gets(s1);
 printf("Enter string 2 :-  ");
 gets(s2);
 c=strcmp(s1,s2);
 if (c==0)
  printf("Strings are similar.");
 else if (a>b)
 {
  printf("Strings are not similar.");
  printf("First string is lenthier than the second string.");
 }
 else if (b>a)
 {
  printf("Strings are not similar.");
  printf("First string is shorter than the second string.");
 }
 else
  printf("Strings are not similar though they are equal in length.");
 getch();
}

 int strcmp(char s[],char t[])
 {
   int i;
   a=strlen(s1);
   b=strlen(s2);
  if (a>b)
  {
  for(i=0;*s!=')
}