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/* -------------------------------------------------------------------------------
 * int s_isanagram( const char *s, const char *t )
 *
 * -------------------------------------------------------------------------------
 */
int s_isanagram( const char *s, const char *t )
{
	int val = 0, hgram[ 256 ] = {0};		/* histogram for the ASCII table*/
	register char *ps = (char *) s;			/* temp char-pointer to s       */
	register char *pt = (char *) t;			/* temp char-pointer to t       */

	/* sanity checks */
	if ( !s || !t ) { errno = EFAULT; return 0; }
	if ( !*s || !*t ) { errno = EINVAL; return 0; }

	memset( hgram, 0, 256 * sizeof(int) );		/* clear histogram              */
	for (; *s || *t; ) {				/* update histogram             */
		if ( *s )				/* ...                          */
			hgram[(int)*s++]++;		/* ... +1 for every char in s   */
		if ( *t )				/* ...                          */
			hgram[(int)*t++]--;		/* ... -1 for every char in t   */
	}
							/* check in histogram for       */
	while( *ps && *pt++ && !(val=hgram[(int)*ps++]) )/* 1st non-zero mapped val     */
		;					/* of all chars in s            */
	return val || *pt ? 0 : 1;			/* val || *pt != 0 ? FALSE:TRUE */

}