Question

请帮助我。我不知道如何解决这个错误。

Program Polynomial;

type
    arrayOfInt = Array[1..21] of Integer;
    biggerArrayOfInt = Array[1..41] of Integer;

function isNumber(c : Char): Boolean;
var
    res : Boolean;
    code : Longint;
begin
    code := Ord(c);
    if ((code > 47) AND (code < 58)) then begin
        res := true
    end
    else
    begin
        res := false;
    end;
    isNumber := res;
end;

function parsePolynomial(polynomial : String): arrayOfInt;
var
    coeficients : Array[1..21] of Integer;
    number : Integer;
    coef : Integer;
    tmp : String;
    i, j : Integer;
    positive : Boolean;
    numberPosition, numberLength : Integer;
    expectX : Boolean;
begin
    i := 1;
    for j:=1 to Length(coeficients) do
    begin
        coeficients[j] := 0;
    end;
    while (true) do
    begin
        coef := 0;
        number := 0;
        positive := true;
        expectX := true;
        if(polynomial[i] = '-') then begin
            positive := false;
            i := i + 1;
        end;
        if(polynomial[i] = '+') then begin
            i := i + 1;
        end;
        if(isNumber(polynomial[i])) then begin
            numberPosition:= i;
            while (isNumber(polynomial[i])) do
            begin
                i := i + 1;
            end;
            tmp := Copy(polynomial, numberPosition, i - numberPosition);
            Val(tmp, number);
            if(not positive) then begin
                number := number * -1;
            end;

            if ((not(polynomial[i] = '*')) OR (i > length(polynomial))) then
                    begin
                expectX := false;
            end
            else
            begin
                i:= i + 1;
            end;
        end
        else
        begin
            if(positive) then begin
                number := 1;
            end
            else
            begin
                number := -1;
            end;
        end;

        if (expectX) then begin
            if(not(polynomial[i] = 'x')) then begin
                write('Bad input!');
                exit;
            end
            else
            begin
                i := i + 1;
                if (polynomial[i] = '^') then begin
                    i := i + 1;
                    if (not isNumber(polynomial[i])) then begin
                        write('Bad input!');
                        exit;
                    end;
                    numberPosition:= i;
                    while (isNumber(polynomial[i])) do
                    begin
                        i := i + 1;
                    end;
                    tmp := Copy(polynomial, numberPosition, i - numberPosition);
                    Val(tmp, coef);
                end
                else
                begin
                    coef := 1;
                end;
            end;
        end;

        coeficients[coef + 1] := number;

        if ((length(polynomial)) - 1 < i) then begin
            break;
        end;
    end;
   parsePolynomial := coeficients;
end;

function sumPolynomial(polynomial1, polynomial2 : array of Integer): arrayOfInt;
var
    coeficients : Array[1..21] of Integer;
    i : Integer;
begin
    for i := Length(polynomial1) downto 0 do
    begin
        coeficients[i+1] := polynomial1[i] + polynomial2[i];
    end;
    sumPolynomial := coeficients;
end;

function productOfPolynomial(polynomial1, polynomial2 : array of Integer): biggerArrayOfInt;
var
    coeficients : Array[1..41] of Integer;
    i, j : Integer;
begin
    for j:=1 to Length(coeficients) do
    begin
        coeficients[j] := 0;
    end;
    for i := Length(polynomial1) downto 0 do
    begin
        for j := Length(polynomial2) downto 0 do
        begin
                coeficients[i+j+1] := coeficients[i+j+1] + polynomial1[i] * polynomial2[j];
        end;
    end;
    productOfPolynomial := coeficients;
end;

function substractOfPolynomial(polynomial1, polynomial2 : array of Integer): arrayOfInt;
var
    coeficients : Array[1..21] of Integer;
    i : Integer;
begin

    for i := Length(polynomial1) downto 0 do
    begin
        coeficients[i+1] := polynomial1[i] - polynomial2[i];
    end;

   substractOfPolynomial := coeficients;
end;


procedure printPolynomial(polynomial: array of Integer);
var 
    i : Integer;
    isFirst : Boolean;
    isZero : Boolean;
begin
    isFirst := true;
    isZero := true;
    for i := length(polynomial) downto 0 do
    begin
        if polynomial[i] <> 0 then begin
            isZero := false;
            if((not isFirst) AND (polynomial[i] > 0)) then begin
                write('+');
            end;
            if((polynomial[i] = -1)) then begin
                write('-');
            end;
            if(((polynomial[i] > 1) OR (polynomial[i] < -1)) OR ((i = 0) AND not(polynomial[i] = 0))) then begin
                write(polynomial[i]);
                if((i > 0)) then begin
                    write('*');
                end;
            end;

            if(i > 0) then begin
                write('x');
                isFirst := false;
                if (i > 1) then begin
                    write('^', i);
                end;
            end;
            write()
        end;
    end;
    if (isZero) then begin
        write(0);
    end;

end;

var
    polynomial1, polynomial2, result: Array[1..21] of Integer;
    polynomialInput: String;

begin
    readln(polynomialInput);
    polynomial1 := parsePolynomial(polynomialInput);

    readln(polynomialInput);
    polynomial2 := parsePolynomial(polynomialInput);

    printPolynomial(sumPolynomial(polynomial1, polynomial2));
    writeln('');
    printPolynomial(substractOfPolynomial(polynomial1, polynomial2));
    writeln('');
    printPolynomial(productOfPolynomial(polynomial1, polynomial2));
end.

Answer 1

运行时错误201表示范围检查错误。快速浏览一下源代码会让我怀疑某个操作返回一个不适合整数范围的值（默认情况下为FreePascal中的-32786..32767）。最简单的解决方案是使用更大的数据类型，例如longint（大致在-2 * 10 ^ 9..2 * 10 ^ 9之间）或int64（~9 * 10 ^ 18..9 * 10 ^ 18）。

如果使用命令行编译器使用-gl命令行选项，则会在运行时错误回溯中显示行号。这将使您更容易查明问题。

如何修复运行时错误201

1 个答案: