【leetcode】20. 有效的括号

有效的括号题目链接
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// 栈结构
typedef char valuetype;
typedef struct {valuetype* arr;int top;int capacity;
} Stack;void Init(Stack* stack);void Push(Stack* stack, valuetype value);
void Pop(Stack* stack);valuetype Top(Stack* stack);
int Size(Stack* stack);
bool Empty(Stack* stack);void Destroy(Stack* stack);bool isValid(char* s) {Stack stack;Init(&stack);while (*s) {if (*s == '(' || *s == '[' || *s == '{') {Push(&stack, *s); // 1.左括号入栈；}else { // 2.比较。if (Empty(&stack)) { // 2.1右括号比左括号多Destroy(&stack);return false;}else { // 2.2 比较左括号与右括号是否匹配char ch = Top(&stack);Pop(&stack);if ((ch == '(' && *s != ')') ||(ch == '[' && *s != ']') ||(ch == '{' && *s != '}')) {Destroy(&stack);return false;}}}s++;}// 如果栈里还剩有括号，说明左右括号没有对应bool res = Empty(&stack);Destroy(&stack);return res;
}void Init(Stack* stack) {assert(stack);stack->arr = NULL;stack->capacity = stack->top = 0;
}void Push(Stack* stack, valuetype value) {assert(stack);if (stack->top == stack->capacity) {stack->capacity = stack->capacity == 0 ? 10 : (int)(stack->capacity * 1.5);stack->arr = (valuetype*)realloc(stack->arr, sizeof(valuetype) * stack->capacity);if (stack->arr == NULL) {perror("realloc failed in the function Push(Stack*, valuetype).");return;}}stack->arr[stack->top++] = value;
}void Pop(Stack* stack) {assert(stack && stack->top > 0);stack->top--;
}valuetype Top(Stack* stack) {assert(stack && stack->top > 0);return stack->arr[stack->top - 1];
}int Size(Stack* stack) {assert(stack);return stack->top;
}bool Empty(Stack* stack) {assert(stack);return stack->top == 0;
}void Destroy(Stack* stack) {assert(stack);free(stack->arr);stack->arr = NULL;stack->capacity = stack->top = 0;
}