Answer:
Explanation:
The following code is written in C and does what the question requires. It uses the input file reads it and outputs the number of vowels to the file called output.dat
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int str_count_in_chars(char *start, char *end, char *chars) {
int count = 0;
for (; start != end; count += !!strchr(chars, *(start++)));
return count;
}
void str_swap_in_chars(size_t str_len, char **str, char *chars) {
for (int front = 0, back = str_len - 1; front < back; front++) {
if (strchr(chars, (*str)[front])) {
for (; !strchr(chars, (*str)[back]); back--);
char tmp = (*str)[front];
(*str)[front] = (*str)[back];
(*str)[back--] = tmp;
}
}
}
char *file_to_str(FILE *fin) {
int buf_len = 64;
char buf[buf_len];
char *str = malloc(buf_len);
str[0] = '\0';
for (int i = 1; fgets(buf, buf_len, fin); i++) {
if (!(str = realloc(str, i * buf_len))) {
fprintf(stderr, "%s:%d realloc failed\n", __FILE__, __LINE__);
exit(1);
}
strcat(str, buf);
}
return str;
}
int main() {
char *vowels = "aeiou";
FILE *fin = fopen("input.dat", "r");
FILE *fout = fopen("output.dat", "w");
if (!fin || !fout) {
fprintf(stderr, "%s:%d fopen failed\n", __FILE__, __LINE__);
exit(1);
}
char *words = file_to_str(fin);
fclose(fin);
int words_len = strlen(words);
for (int i = 0; i < words_len;) {
if (isspace(words[i])) {
fputc(words[i++], fout);
continue;
}
int start = i;
for (; i < words_len && !isspace(words[i]); i++);
char *word = words + start;
int word_len = i - start;
int vowel_count = str_count_in_chars(word, words + i, vowels);
if (vowel_count % 2 == 0) {
str_swap_in_chars(word_len, &word, vowels);
}
fprintf(fout, "%.*s_%dvow", word_len, word, vowel_count);
}
fclose(fout);
free(words);
return 0;
}
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