Non repeated or unique characters in String(Case Insensitive)

 

Printing Non-repeated or Unique Characters Using C program(Case Insensitive)

Printing Unique characters from the string:

C Program:

#include <stdio.h> #include <string.h> int main() { char a[100]; int i,j,count; printf("Enter the string:"); gets(a); for(i=0;i<strlen(a);i++) { count=0; for(j=i+1;j<strlen(a);j++) { if(tolower(a[i])==tolower(a[j])&&a[i]!=' ') { count++; a[j]='0'; } } if(count>0) { a[i]='0'; } } printf("After removing the duplicate character, the string: "); 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,

for(j=i+1;j<strlen(a);j++){ if(tolower(a[i])==tolower(a[j])&&a[i]!=' ') { count++; a[j]='0'; } }

ü a[i] is the character used for comparing.

ü a[j] is the character to be compared with a[i].

ü For every i increament, the count is initialized to 0, count gets increased whenever the character used for comparing gets repeated i.e a[i].

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.

if(count>0) { a[i]='0'; }

ü When the count is greater than 0 it indicates that a[i] occurs more than 1 time, then it  assigns the value '0' to a[i].

ü So, the repeated characters are assigned to the value '0'.

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 dandelions as 0a00elio0s.

Note: Printing Non-Repeated or Unique characters from the string (Case Sensitive)