(*
Copyright 2016 Anton Krotov
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*)
MODULE In;
IMPORT sys := SYSTEM, ConsoleLib;
TYPE
STRING = ARRAY 260 OF CHAR;
VAR
Done* : BOOLEAN;
PROCEDURE digit(ch: CHAR): BOOLEAN;
RETURN (ch >= "0") & (ch <= "9")
END digit;
PROCEDURE CheckInt(s: STRING; VAR first, last: INTEGER; VAR neg: BOOLEAN; Point: BOOLEAN): BOOLEAN;
VAR i: INTEGER;
BEGIN
i := 0;
neg := FALSE;
WHILE (s[i] <= 20X) & (s[i] # 0X) DO
INC(i)
END;
IF s[i] = "-" THEN
neg := TRUE;
INC(i)
ELSIF s[i] = "+" THEN
INC(i)
END;
first := i;
WHILE digit(s[i]) DO
INC(i)
END;
last := i
RETURN ((s[i] <= 20X) OR (Point & (s[i] = "."))) & digit(s[first])
END CheckInt;
PROCEDURE IsMinInt(str: STRING; pos: INTEGER): BOOLEAN;
VAR i: INTEGER; min: STRING;
BEGIN
i := 0;
min := "2147483648";
WHILE (min[i] # 0X) & (str[i] # 0X) & (min[i] = str[i + pos]) DO
INC(i)
END
RETURN i = 10
END IsMinInt;
PROCEDURE StrToInt(str: STRING; VAR err: BOOLEAN): INTEGER;
CONST maxINT = 7FFFFFFFH;
VAR i, n, res: INTEGER; flag, neg: BOOLEAN;
BEGIN
res := 0;
flag := CheckInt(str, i, n, neg, FALSE);
err := ~flag;
IF flag & neg & IsMinInt(str, i) THEN
flag := FALSE;
neg := FALSE;
res := 80000000H
END;
WHILE flag & digit(str[i]) DO
IF res > maxINT DIV 10 THEN
err := TRUE;
flag := FALSE;
res := 0
ELSE
res := res * 10;
IF res > maxINT - (ORD(str[i]) - ORD("0")) THEN
err := TRUE;
flag := FALSE;
res := 0
ELSE
res := res + (ORD(str[i]) - ORD("0"));
INC(i)
END
END
END;
IF neg THEN
res := -res
END
RETURN res
END StrToInt;
PROCEDURE Space(s: STRING): BOOLEAN;
VAR i: INTEGER;
BEGIN
i := 0;
WHILE (s[i] # 0X) & (s[i] <= 20X) DO
INC(i)
END
RETURN s[i] = 0X
END Space;
PROCEDURE CheckReal(s: STRING; VAR n: INTEGER; VAR neg: BOOLEAN): BOOLEAN;
VAR i: INTEGER; Res: BOOLEAN;
BEGIN
Res := CheckInt(s, n, i, neg, TRUE);
IF Res THEN
IF s[i] = "." THEN
INC(i);
WHILE digit(s[i]) DO
INC(i)
END;
IF (s[i] = "D") OR (s[i] = "E") OR (s[i] = "d") OR (s[i] = "e") THEN
INC(i);
IF (s[i] = "+") OR (s[i] = "-") THEN
INC(i)
END;
Res := digit(s[i]);
WHILE digit(s[i]) DO
INC(i)
END
END
END
END
RETURN Res & (s[i] <= 20X)
END CheckReal;
PROCEDURE StrToFloat(str: STRING; VAR err: BOOLEAN): LONGREAL;
CONST maxDBL = 1.69D308; maxINT = 7FFFFFFFH;
VAR i, scale: INTEGER; res, m, d: LONGREAL; minus, neg: BOOLEAN;
PROCEDURE part1(): BOOLEAN;
BEGIN
res := 0.0D0;
d := 1.0D0;
WHILE digit(str[i]) DO
res := res * 10.0D0 + LONG(FLT(ORD(str[i]) - ORD("0")));
INC(i)
END;
IF str[i] = "." THEN
INC(i);
WHILE digit(str[i]) DO
d := d / 10.0D0;
res := res + LONG(FLT(ORD(str[i]) - ORD("0"))) * d;
INC(i)
END
END
RETURN str[i] # 0X
END part1;
PROCEDURE part2(): BOOLEAN;
BEGIN
INC(i);
m := 10.0D0;
minus := FALSE;
IF str[i] = "+" THEN
INC(i)
ELSIF str[i] = "-" THEN
minus := TRUE;
INC(i);
m := 0.1D0
END;
scale := 0;
err := FALSE;
WHILE ~err & digit(str[i]) DO
IF scale > maxINT DIV 10 THEN
err := TRUE;
res := 0.0D0
ELSE
scale := scale * 10;
IF scale > maxINT - (ORD(str[i]) - ORD("0")) THEN
err := TRUE;
res := 0.0D0
ELSE
scale := scale + (ORD(str[i]) - ORD("0"));
INC(i)
END
END
END
RETURN ~err
END part2;
PROCEDURE part3;
VAR i: INTEGER;
BEGIN
err := FALSE;
IF scale = maxINT THEN
err := TRUE;
res := 0.0D0
END;
i := 1;
WHILE ~err & (i <= scale) DO
IF ~minus & (res > maxDBL / m) THEN
err := TRUE;
res := 0.0D0
ELSE
res := res * m;
INC(i)
END
END
END part3;
BEGIN
IF CheckReal(str, i, neg) THEN
IF part1() & part2() THEN
part3
END;
IF neg THEN
res := -res
END
ELSE
res := 0.0D0;
err := TRUE
END
RETURN res
END StrToFloat;
PROCEDURE String*(VAR s: ARRAY OF CHAR);
VAR res, length: INTEGER; str: STRING;
BEGIN
res := ConsoleLib.gets(sys.ADR(str[0]), LEN(str));
length := LENGTH(str);
IF length > 0 THEN
str[length - 1] := 0X
END;
COPY(str, s);
Done := TRUE
END String;
PROCEDURE Char*(VAR x: CHAR);
VAR str: STRING;
BEGIN
String(str);
x := str[0];
Done := TRUE
END Char;
PROCEDURE Ln*;
VAR str: STRING;
BEGIN
String(str);
Done := TRUE
END Ln;
PROCEDURE LongReal*(VAR x: LONGREAL);
VAR str: STRING; err: BOOLEAN;
BEGIN
err := FALSE;
REPEAT
String(str)
UNTIL ~Space(str);
x := StrToFloat(str, err);
Done := ~err
END LongReal;
PROCEDURE Real*(VAR x: REAL);
CONST maxREAL = 3.39E38;
VAR y: LONGREAL;
BEGIN
LongReal(y);
IF Done THEN
IF ABS(y) > LONG(maxREAL) THEN
x := 0.0;
Done := FALSE
ELSE
x := SHORT(y)
END
END
END Real;
PROCEDURE Int*(VAR x: INTEGER);
VAR str: STRING; err: BOOLEAN;
BEGIN
err := FALSE;
REPEAT
String(str)
UNTIL ~Space(str);
x := StrToInt(str, err);
Done := ~err
END Int;
PROCEDURE Open*;
BEGIN
Done := TRUE
END Open;
END In.