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/*
* TASK #1 - Four Is Magic - done in C.
* MY NOTES: ok. Pretty easy.
*/
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>
char *n_to_word[] = {
"zero",
"one",
"two",
"three",
"four",
"five",
"six",
"seven",
"eight",
"nine"
};
bool debug = false;
/*
* int n = process_args( argc, argv );
* Process cmd line options (setting debug if --debug/-d option given)
* and the optional value n (default 3), return n.
* My goodness, it's painful to write this sort of code..
*/
int process_args( int argc, char **argv )
{
int pos = 1;
if( argc > 1 &&
(strcmp( argv[1], "--debug" )==0 || strcmp( argv[1], "-d")==0 ) )
{
debug = true;
pos++;
}
if( argc < pos )
{
fprintf( stderr,
"Usage: four-is-magic [--debug] [N] (default 3, < 10)\n" );
exit(1);
}
int n = argc > pos ? atoi( argv[pos] ) : 3;
if( n==0 ) n = 3;
if( n < 0 || n > 9 )
{
fprintf( stderr, "four-is-magic: n ($n) must be 0..9\n" );
exit(1);
}
return n;
}
int main( int argc, char **argv )
{
int n = process_args( argc, argv );
char *word = n_to_word[n];
char answer[512];
char *p = answer;
while( strcmp( word, "four") != 0 )
{
int len = strlen(word);
char *lenword = n_to_word[len];
strcpy( p, word );
strcat( p, " is " );
strcat( p, lenword );
strcat( p, ", " );
p += strlen(p);
if( debug )
{
printf( "debug: word=%s, len=%d, lenword=%s, "
"added '%s is %s'\n",
word, len, lenword, word, lenword );
}
word = lenword;
}
strcpy( p, "four is magic." );
puts( answer );
return 0;
}
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