learn_c/intro/ex1_19.c

49 lines
906 B
C

#include <stdio.h>
#define MAXLINE 1000 /* maximum input line size */
int get_line(char line[], int maxline);
void myreverse(char to[], char from[], int len);
/* print longest input line */
main()
{
int len;
char line[MAXLINE];
char reverse_line[MAXLINE];
while ((len = get_line(line, MAXLINE)) > 0) {
myreverse(reverse_line, line, len);
printf("%s", reverse_line);
}
return 0;
}
/* getline: read a line into s, return length */
int get_line(char s[], int lim)
{
int c, i;
for (i = 0; i < lim-1 && (c = getchar()) != EOF && c != '\n'; ++i)
s[i] = c;
if (c == '\n') {
s[i] = c;
++i;
}
s[i] = '\0';
return i;
}
/* reverse: reverse a char string */
void myreverse(char to[], char from[], int len)
{
int i;
to[len] = '\0';
to[len-1] = '\n';
for (i = 0; i < len-1; ++i)
to[len-2-i] = from[i];
// printf("%s", from);
// printf("%s", to);
}