C Programming Code Examples
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program to remove all repeated characters in a string
/* program to remove all repeated characters in a string
Write a C program to remove all repeated characters in a string using loops. How to remove all duplicate characters from a string using for loop in C programming. Program to find and remove all duplicate characters in a string. Logic to remove all repeated character from string in C program.
Logic to remove repeated characters from string
Input string from user, store it in some variable say str.
Run a loop from start to end character of the given string str.
For each character ch in the string, remove all next occurrences of ch. */
#include <stdio.h>
#define maxsize 100 // Maximum string size
/* Function declarations */
void removeDuplicates(char * str);
void removeAll(char * str, const char toRemove, int index);
int main()
{
char str[maxsize];
/* Input string from user */
printf("Enter any string: ");
gets(str);
printf("String before removing duplicates: %s\n", str);
removeDuplicates(str);
printf("String after removing duplicates: %s\n", str);
return 0;
}
/* Remove all duplicate characters from the given string */
void removeDuplicates(char * str)
{
int x = 0;
while(str[x] != '\0')
{
/* Remove all duplicate of character string[x] */
removeAll(str, str[x], x + 1);
x++;
}
}
/* Remove all occurrences of a given character from string. */
void removeAll(char * str, const char toRemove, int index)
{
int x;
while(str[index] != '\0')
{
/* If duplicate character is found */
if(str[index] == toRemove)
{
/* Shift all characters from current position to one place left */
x = index;
while(str[x] != '\0')
{
str[x] = str[x + 1];
x++;
}
}
index++;
}
}
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