关于栈的应用 （括号匹配）
对于一个字符串 用栈的数据结构去判断括号是否匹配 这是对栈的应用 也是对栈理解的更一步深入
定义结构体
typedef struct CharStack {
int top;
//栈顶参数
int data[STACK_MAX_SIZE];
//栈数组
} *CharStackPtr;
打印栈
void outputStack(CharStackPtr paraStack) {
//循环打印栈
for (int i = 0; i <= paraStack->top; i ++) {
printf("%c ", paraStack->data[i]);
}
printf("rn");
}
申请空间栈
CharStackPtr charStackInit() {
//动态开辟天地
CharStackPtr resultPtr = (CharStackPtr)malloc(sizeof(struct CharStack));
resultPtr->top = -1;//-1尾巴
return resultPtr;
}
存放数据
void push(CharStackPtr paraStackPtr, int paraValue) {
//一样存储数据
if (paraStackPtr->top >= STACK_MAX_SIZE - 1) {
printf("Cannot push element: stack full.rn");
return;
}//Of if
// 栈顶数量++
paraStackPtr->top ++;
// 存储
paraStackPtr->data[paraStackPtr->top] = paraValue;
}
取出数据
char pop(CharStackPtr paraStackPtr) {
// 判断是否合法取数据
if (paraStackPtr->top < 0) {
printf("Cannot pop element: stack empty.rn");
return ' ';
}
//取出数量--
paraStackPtr->top --;
// 打印数据
return paraStackPtr->data[paraStackPtr->top + 1];
}
存放取出测试
void pushPopTest() {
printf("---- pushPopTest begins. ----rn");
CharStackPtr tempStack = charStackInit();
printf("After initialization, the stack is: ");
outputStack(tempStack);
for (char ch = 'a'; ch < 'm'; ch ++) {
printf("Pushing %c.rn", ch);
push(tempStack, ch);
outputStack(tempStack);
}
for (int i = 0; i < 3; i ++) {
char ch = pop(tempStack);
printf("Pop %c.rn", ch);
outputStack(tempStack);
}
printf("---- pushPopTest ends. ----rn");
}
重头戏----括号匹配代码
bool bracketMatching(char *paraString, int paraLength) {
CharStackPtr tempStack = charStackInit();
push(tempStack, '#');
//栈底放个# 来表示低
char tempChar, tempPopedChar;
for (int i = 0; i < paraLength; i++) {
tempChar = paraString[i];
switch (tempChar) {
//遍历到这种直接按顺序存入栈
case '(':
case '[':
case '{':
push(tempStack, tempChar);
break;
case ')':
//判断
tempPopedChar = pop(tempStack);
//栈顶如果不与之匹配 那就有问题
if (tempPopedChar != '(') {
return false;
}
break;
case ']':
tempPopedChar = pop(tempStack);
//同理
if (tempPopedChar != '[') {
return false;
}
break;
case '}':
tempPopedChar = pop(tempStack);
if (tempPopedChar != '{') {
return false;
}
break;
default:
// 啥也不干
break;
}
}
tempPopedChar = pop(tempStack);
if (tempPopedChar != '#') {
return true;
}
//成功匹配返回1
return true;
}
括号匹配测试代码
void bracketMatchingTest() {
char *tempExpression = "[2 + (1 - 3)] * 4";
bool tempMatch = bracketMatching(tempExpression, 17);
printf("Is the expression '%s' bracket matching? %d rn", tempExpression, tempMatch);
tempExpression = "( ) )";
tempMatch = bracketMatching(tempExpression, 6);
printf("Is the expression '%s' bracket matching? %d rn", tempExpression, tempMatch);
tempExpression = "()()(())";
tempMatch = bracketMatching(tempExpression, 8);
printf("Is the expression '%s' bracket matching? %d rn", tempExpression, tempMatch);
tempExpression = "({}[])";
tempMatch = bracketMatching(tempExpression, 6);
printf("Is the expression '%s' bracket matching? %d rn", tempExpression, tempMatch);
tempExpression = ")(";
tempMatch = bracketMatching(tempExpression, 2);
printf("Is the expression '%s' bracket matching? %d rn", tempExpression, tempMatch);
}
int main() {
bracketMatchingTest();
}
运行截图
