implement Base64;include "base64.m"; PADCH: con '=';encode(b: array of byte): string{	chmap := "ABCDEFGHIJKLMNOPQRSTUVWXYZ" +			"abcdefghijklmnopqrstuvwxyz0123456789+/";	r := "";	blen := len b;	full := (blen + 2)/ 3;	rplen := (4*blen + 2) / 3;	ip := 0;	rp := 0;	for (i:=0; i<full; i++) {		word := 0;		for (j:=2; j>=0; j--)			if (ip < blen)				word = word | int b[ip++] << 8*j;		for (l:=3; l>=0; l--)			if (rp < rplen)				r[rp++] = chmap[(word >> (6*l)) & 16r3f];			else				r[rp++] = PADCH;	}	return r;} # Decode a base 64 string to a byte stream# Must be a multiple of 4 characters in lengthdecode(s: string): array of byte{ 	tch: int;	slen := len s;	rlen := (3*slen+3)/4;	if (slen >= 4 && s[slen-1] == PADCH)		rlen--;	if (slen >= 4 && s[slen-2] == PADCH)		rlen--;	r := array[rlen] of byte;	full := slen / 4;	sp := 0;	rp := 0;	for (i:=0; i<full; i++) {		word := 0; 		for (j:=0; j<4; j++) {			ch := s[sp++];			case ch {			'A' to 'Z' =>				tch = ch - 'A';			'a' to 'z' =>				tch = ch - 'a' + 26;			'0' to '9' =>				tch = ch - '0' + 52;			'+' =>				tch = 62;			'/' =>				tch = 63;			* =>				tch = 0;			}			word = (word << 6) | tch;		}		for (l:=2; l>=0; l--)			if (rp < rlen)				r[rp++] = byte( (word >> 8*l) & 16rff); 	}	return r;}