How to clear input buffer after fgets overflow?

How to clear input buffer after fgets overflow?

I'm facing a little problem with fgets when the input string exceeds its
predefined limit.
Taking the example below:
for(index = 0; index < max; index++)
{
printf(" Enter the %d th string :",index);
while ((ch = getchar()) != '\n' && ch != EOF); //An attempt to clear
buffer
if(fgets(input,MAXLEN,stdin))
{
removeNewLine(input);
if(strcmp(input,"end") != 0)
// Do something with input
}
}
Now when I exceed the length MAXLEN and enter a string, I know that the
input will append a '\0' at MAXLEN -1 and that would be it. The problem
happens when I try to enter the 2nd string which is not asked for i.e
Output :
Enter the first string : Aaaaaaaaaaaaaaaaaaaa //Exceeds limit
Enter the second string : Enter the third string : ....Waits input
So, I thought I should clear the buffer the standard way as in C. It waits
until I enter
return
two times, The first time it being appended to the string and the next
time,acting as end of input.
Is there any method by which I can clear the buffer without entering the
extra return?
How do I implement error handling for the same? Because the fgets return
value will be Non-null and strlen(input) gives me the accepted size of the
string by fgets, what should be done?
Thanks a lot