#include <stdio.h>
#include <stdlib.h>
#include <string.h>

char* expand_tabs(const char* string);

int main(void)
{
	const char* str = "This is a text	This is another one. ' ' <- space; '	' <-tab";
	printf("%s - %d\n", str, (int)strlen(str));
	printf("%s - %d\n", expand_tabs(str),(int) strlen(expand_tabs(str)));
	
}

char* expand_tabs(const char* string){
	int tab_count = 0, letter_count = 0;
	for(int i = 0; string[i] != '\0'; i++){
		letter_count++;
		if(string[i] == '\t')
			tab_count++;
	}
	char* ret = malloc(sizeof(char) * letter_count + 3*tab_count);
	char* filler = ret;
	for(int i = 0; string[i] != '\0'; i++){
		if(string[i] == '\t'){
			for (int j = 0; j < 4; ++j) {
				*(filler++) = ' ';
			}
		}else{
			*(filler++) = string[i];
		}
	}
	return ret;
}