1-16.c

#include <stdio.h>
#define MAXLINE 1000

int getline(char line[], int maxline);
void copy(char to[], char from[]);

int main(void)
{
  int len;
  int max;
  char line[MAXLINE];
  char longset[MAXLINE];

  max = 0;
  while ((len = getline(line, MAXLINE)) > 0)
  {
    if (len > max)
    {
      max = len;
      copy(longset, line);
    }
  }
  if (max > 0)
    printf("%s", longset);

  return 0;
}

int getline(char s[], int lim)
{
  int i, c;

  for (i = 0;
       i < lim - 1 && (c = getchar()) != EOF && c != '\n';
       ++i)
    s[i] = c;

  if (c == '\n')
    s[i] = c;
  s[i + 1] = '\0';
  if (c != EOF && c != '\n')
    while (c != '\n' && (c = getchar()) != EOF)
      ++i;


  return i;
}

void copy(char to[], char from[])
{
  int i;

  i = 0;
  while ((to[i] = from[i]) != '\0')
    ++i;
}