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C Program to Remove Last Occurrence of a Character in a String

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Write a C Program to Remove Last Occurrence of a Character in a String with example.

C Program to Remove Last Occurrence of a Character in a String Example 1

This program allows the user to enter a string (or character array), and a character value. Next, this C program will find and remove last occurrence of a character inside a string.

/* C Program to Remove Last Occurrence of a Character in a String */
 
#include <stdio.h>
#include <string.h>
 
int main()
{
  	char str[100], ch;
  	int i, index, len;
  	index = -1;
 
  	printf("\n Please Enter any String :  ");
  	gets(str);
  	
  	printf("\n Please Enter the Character that you want to Search for :  ");
  	scanf("%c", &ch);
  	
	len  = strlen(str);
  	
  	for(i = 0; i < len; i++)
  	{
  		if(str[i] == ch)  
		{
  			index = i;	
 		}
	}
    if(index != -1)
  	{ 		
  		i = index;
  	
	  	while(i < len)
  		{
  			str[i] = str[i + 1];
			i++;  
		}
	}

	printf("\n The Final String after Removing Last Occurrence of '%c' = %s ", ch, str);	
  	return 0;
}

OUTPUT

C Program to Remove Last Occurrence of a Character in a String 1

ANALYSIS

First, we used For Loop to iterate each character in a String. Within the loop, we are checking whether the individual character is equal to a user-specified character or not. If True, then we are assigning i value to index variable.

for(i = 0; i < len; i++)
{
	if(str[i] == ch)  
	{
		index = i;  	
	}
}

Next, we used the If Statement to check the index value is not equal to -1. If it is True then compiler will shift the characters
str[] = tutorial
ch = t
Index = -1

For Loop First Iteration: for(i = 0; i < len; i++)
The condition is True because 0 < 8.

Within the While Loop, we used If statement to check whether the str[0] is equal to a given character or not

if(str[i] == ch) => if(t == t) – condition is True. So,
index  = i = 0.

Second Iteration: for(i = 1; 1 < 8; 1++)
if(str[1] == ch) => if(u == l) – condition is false. So, i will be incremented.

Third Iteration: for(i = 2; 2 <= 5; 2++)
if(str[i] == ch) => if(t == t) – condition is True.
Index  = i
index  = 2

Do the same for remaining iterations.

Next, we used the If Statement to check the index value is not equal to -1. Here, the condition is True so, i = index
i = 2

While Loop First Iteration: while(i < len)
=> while(2 < 8) – Condition is True
str[i] = str[i + 1]
str[2] = str[3]
str[2] = o
i will be incremented

Second Iteration: while(3 < 8)
str[3] = str[4]
str[3] = r
i will increment

Third Iteration: while(4 < 8)
str[4] = str[5]
str[4] = i
i will increment

Do the same for remaining iterations until i becomes 8.

At last, we used the printf statement to print the final string

printf("\n The Last Occurrence of the Search Element '%c' is at Position %d ", ch, i + 1);

C Program to Remove Last Occurrence of a Character in a String Example 2

This program to remove the last occurrence of a character is the same as the above. Here, we just replaced the For Loop with While Loop.

/* C Program to Remove Last Occurrence of a Character in a String */
 
#include <stdio.h>
#include <string.h>
 
int main()
{
  	char str[100], ch;
  	int i, index, len;
  	index = -1;
  	i = 0;
 
  	printf("\n Please Enter any String :  ");
  	gets(str);
  	
  	printf("\n Please Enter the Character that you want to Search for :  ");
  	scanf("%c", &ch);
  	
	len  = strlen(str);
  	
  	while(i < len)
  	{
  		if(str[i] == ch)  
		{
  			index = i;	
 		}
 		i++;
	}
    if(index != -1)
  	{ 		
  		i = index;
  	
	  	while(i < len)
  		{
  			str[i] = str[i + 1];
			i++;  
		}
	}

	printf("\n The Final String after Removing Last Occurrence of '%c' = %s ", ch, str);	
  	return 0;
}

OUTPUT

C Program to Remove Last Occurrence of a Character in a String 2

C Program to Remove Last Occurrence of a Character in a String Example 3

This program to remove the last character occurrence is the same as the first example. Still, this time, we used the Functions concept to separate the logic.

/* C Program to Remove Last Occurrence of a Character in a String */
 
#include <stdio.h>
#include <string.h>

void Remove_LastOccurrence(char *str, char ch);
 
int main()
{
  	char str[100], ch;
 
  	printf("\n Please Enter any String :  ");
  	gets(str);
  	
  	printf("\n Please Enter the Character that you want to Search for :  ");
  	scanf("%c", &ch);
  	
	Remove_LastOccurrence(str, ch);

	printf("\n The Final String after Removing Last Occurrence of '%c' = %s ", ch, str);	
  	return 0;
}

void Remove_LastOccurrence(char *str, char ch)
{
	int i, index, len;
	
	len = strlen(str);
	
	for(i = 0; i < len; i++)
  	{
  		if(str[i] == ch)  
		{
  			index = i;	
 		}
	}
	
    if(index != -1)
  	{ 		
  		i = index;
  	
	  	while(i < len)
  		{
  			str[i] = str[i + 1];
			i++;  
		}
	}
}

OUTPUT

C Program to Remove Last Occurrence of a Character in a String 3