Leetcode—20.有效的括号【简单】

2023每日刷题（二十七）

Leetcode—20.有效的括号

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C++实现代码

class Solution {
public:bool isValid(string s) {stack<char> arr;int len = s.size();if(len == 1) {return false;}for(int i = 0; i < len; i++) {if(s[i] == '(' || s[i] == '[' || s[i] == '{') {arr.push(s[i]);} else {if(arr.empty()) {return false;}char t = s[i];char pairBracket = ' ';switch(t) {case ')':pairBracket = '(';break;case ']':pairBracket = '[';break;case '}':pairBracket = '{';break;}if(arr.top() != pairBracket) {return false;} else {arr.pop();}}}if(arr.empty()) {return true;}return false;}
};

运行结果

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C语言实现代码

#define MAXSIZE 10003typedef struct {char data[MAXSIZE];int top;
}SqStack;void InitStack(SqStack *st) {st->top = -1;
}bool stackEmpty(SqStack st) {return st.top == -1;
}bool Push(SqStack *st, char e) {if(st->top == MAXSIZE - 1) {return false;}st->top++;st->data[st->top] = e;return true;
}char Pop(SqStack *st) {char e = st->data[st->top];st->top--;return e;
}char getTop(SqStack st) {return st.data[st.top];
}bool isValid(char* s) {SqStack st;InitStack(&st);int n = strlen(s);for(int i = 0; i < n; i++) {if(s[i] == '(' || s[i] == '[' || s[i] == '{') {Push(&st, s[i]);} else {if(stackEmpty(st)) {return false;}char t = s[i];char pairBracket = ' ';switch(t) {case ')':pairBracket = '(';break;case ']':pairBracket = '[';break;case '}':pairBracket = '{';break;}if(getTop(st) != pairBracket) {return false;} else {Pop(&st);}}}if(stackEmpty(st)) {return true;}return false;
}