30 lines
521 B
ObjectPascal
30 lines
521 B
ObjectPascal
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function GenBracketExpr(n: integer): string;
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begin
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var a := Arr('[',']')*n;
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Shuffle(a);
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Result := a.JoinToString
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end;
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function IsBalanced(s: string): boolean;
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begin
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Result := True;
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var st := new Stack<char>;
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foreach var c in s do
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if c = '[' then
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st.Push(c)
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else if (st.Count > 0) and (st.Peek = '[') then
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st.Pop
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else begin
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Result := False;
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exit
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end;
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end;
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begin
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loop 10 do
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begin
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var s := GenBracketExpr(Random(2,5));
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Println(s, IsBalanced(s));
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end;
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end.
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