LeetCode20-有效的括号
LeetCode20-有效的括号
使用栈
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| public boolean isValid(String s) { Stack<Character> stack = new Stack<>();
for (int i = 0; i < s.length(); i++) { char c = s.charAt(i); if (c == '(' || c == '[' || c == '{') { stack.push(c); } else { if (stack.isEmpty()) { return false; } else { char topChar = stack.pop(); if (c == ')' && topChar != '(') { return false; } if (c == ']' && topChar != '[') { return false; } if (c == '}' && topChar != '{') { return false; } } } }
return stack.isEmpty(); }
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