C program to Remove duplicate Character(Case insensitive)

 

Removing Duplicate Characters Using C program(Case Insensitive)

Removing duplicate character or repeated character from the string (Case Sensitive):

C Program:

#include <stdio.h> #include <string.h> int main() { char a[100]; int i,j; printf("Enter the string:"); gets(a);// get the input from the user for(i=0;i<strlen(a);i++) { for(j=i+1;j<strlen(a);j++) { if(tolower(a[i])==tolower(a[j])&&a[i]!=' ') { a[j]='0'; } } } printf("After removing the duplicate character, the new string: "); //Printing the output for(i=0;i<strlen(a);i++) { if(a[i]!='0') { printf("%c",a[i]); } } return 0; }

Output 1:

Output 2:

From the above program,

{ if(tolower(a[i])==tolower(a[j])&&a[i]!=' ') { a[j]='0'; } }

ü The above lines used to compare the characters in the string one by one, when the repeated character comes then its value is assigned to '0'(a[j]='0').

ü a[i]!='  ', this condition is used to not remove the repeated blank space from the string.

ü tolower() is used to convert the uppercase letters to lowercase letters for comparing. Thus it provides the case insensitive operation for removing the repeated characters.

{ for(i=0;i<strlen(a);i++) { if(a[i]!='0') { printf("%c",a[i]); } }

ü The above lines used to print the final string without '0' value assigned to the repeated character.
ü So this avoid printing CcoLllEge as C0oL00Eg0.

Note: Removing duplicate Character using C program(Case sensitive)