C Programming Code Examples
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program to trim trailing white spaces from a string
/* program to trim trailing white spaces from a string
Write a C program to trim trailing/end white space characters in a string using loop. How to remove trailing blank space characters from a given string using loop in C programming. Logic to delete all trailing white space characters from a given string in C.
Logic to remove trailing white spaces
Logic to remove trailing white space characters is lot more easier and faster than removing leading white space characters. As in this case we need not to perform any character shifting operation.
Input string from user, store it in some variable say str.
Initialize a variable to store last index of a non-white space character, say index = -1.
Run a loop from start of the str till end.
Inside the loop if current character is a non-white space character, then update the index with current character index.
Finally, you will be left with last index of non-white space character. Assign NULL character at str[index + 1] = '\0'. */
#include <stdio.h>
#define maxsize 100 // Maximum string size
/* Function declaration */
void trimTrailing(char * str);
int main()
{
char str[maxsize];
/* Input string from user */
printf("Enter any string: ");
gets(str);
printf("\nString before trimming trailing white space: \n'%s'", str);
trimTrailing(str);
printf("\n\nString after trimming trailing white spaces: \n'%s'", str);
return 0;
}
/* Remove trailing white space characters from string */
void trimTrailing(char * str)
{
int index, i;
/* Find last index of non-white space character */
i = 0;
while(str[i] != '\0')
{
if(str[i] != ' ' && str[i] != '\t' && str[i] != '\n')
{
index= i;
}
i++;
}
/* Mark next character to last non-white space character as NULL */
str[index + 1] = '\0';
}
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Get string from stdin. Reads characters from the standard input (stdin) and stores them as a C string into str until a newline character or the end-of-file is reached. The newline character, if found, is not copied into str. A terminating null character is automatically appended after the characters copied to str. Notice that gets is quite different from fgets: not only gets uses stdin as source, but it does not include the ending newline character in the resulting string and does not allow to specify a maximum size for str (which can lead to buffer overflows).
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