File : Count Character

Write a program to count the number of times a character appears in the File. (Case insensitive... 'a' and 'A' are considered to be the same)

Input and Output Format:
Refer sample input and output for formatting specifications. All text in bold corresponds to input and the rest corresponds to output.

Sample Input and Output: 
Enter the file name test.txt
Enter the character to be counted
r
File 'test.txt' has 99 instances of letter 'r'.

Code:

  #include<stdio.h>
#include<ctype.h>
#include<stdlib.h>
int main(void)
{
  FILE *fptr=NULL;
  char c[2],get;
  int ch;
  int count=0;
  char filename[100];
  printf("Enter the file name\n");
  scanf("%19s",filename);
  fptr=fopen(filename,"r");
  printf("Enter the character to be counted\n");
  scanf(" %s",c);
  
  if(fptr==NULL)
  {
    exit(-1);
  }
  
  if(((int)c[0]>=65)&&((int)c[0]<=122))
  {
    if(((int)c[0]>=97)&&((int)c[0]<=122))
      ch=(int)c[0]-32;
    else
      ch=(int)c[0]+32;
  }
  
  do{
    get=fgetc(fptr);
    if(((int)get==ch)||get==c[0])
      count=count+1;
  }while(get!=EOF);
  
      
  printf("File '%s' has %d instances of letter '%s'.",filename,count,c);
  fclose(fptr);
  return 0;
}