68 lines
1.8 KiB
C#
68 lines
1.8 KiB
C#
using System.Text;
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namespace _20._Valid_Parentheses;
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public class Solution
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{
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public bool IsValid(string s)
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{
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StringBuilder sb = new StringBuilder(s);
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if (sb.Length == 0)
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return true;
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if (sb.Length % 2 == 1)
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return false;
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while (sb.Length > 0)
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{
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char ch = sb[0];
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if ("({[".Contains(ch) == false)
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return false;
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char need = ch switch
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{
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'(' => ')',
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'{' => '}',
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'[' => ']',
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_ => '\0'
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};
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int count1 = 0;// ()
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int count2 = 0;// {}
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int count3 = 0;// []
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bool succes = false;
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for (int i = 1; i < sb.Length; i++)
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{
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char c = sb[i];
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if (count1 == 0 && count2 == 0 && count3 == 0 && c == need)
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{
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sb.Remove(i, 1).Remove(0, 1);
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succes = true;
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break;
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}
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switch (c)
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{
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case '(':
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count1++;
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break;
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case ')':
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count1--;
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break;
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case '{':
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count2++;
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break;
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case '}':
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count2--;
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break;
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case '[':
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count3++;
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break;
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case ']':
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count3--;
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break;
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}
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}
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if (succes == false)
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return false;
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}
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return true;
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}
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} |