更新一部分栈和队列的习题

栈和队列/栈/P71.3.cpp

@@ -0,0 +1,44 @@
+#include <iostream>
+#include <vector>
+using namespace std;
+
+//P71.3
+//假设以I和O分别表示入栈和出栈操作。栈的初态和终态均为空, 入栈和出栈的操作序
+//列可表示为仅由I和O组成的序列, 可以操作的序列称为合法序列, 否则称为非法序列
+//)下面所示的序列中哪些是合法的
+//A.IOlIOIOO 合法
+//B.IOOIOlO
+//C.IIIOIOIO
+//D.IIIOOIOO  合法
+//2)通过对1)的分析, 写出一个算法, 判定所给的操作序列是否合法。若合法, 返回true
+//否则返回 false(假定被判定的操作序列已存入一维数组中)
+
+
+#define _for(i,a,b) for(int i=(a);i<(b);i++)
+
+//P71.3
+bool Legal(vector<char> str) {
+	int size = 0;
+	_for(i, 0, str.size()) {
+		if (str[i] == 'I') {
+			size++;
+		}
+		if (str[i] == 'O') {
+			size--;
+		}
+		if (size < 0)
+			return false;
+	}
+	if (!size)
+		return true;
+}
+
+int main()
+{
+	vector<char> str1 = { 'I','O','I','I','O','I','O','O' };
+	vector<char> str2 = { 'I','O','O','I','O','I','I','O' };
+	cout << Legal(str1) << endl;
+	return 0;
+
+}
+

栈和队列/栈/P71.4.cpp

@@ -0,0 +1,105 @@
+#include <iostream>
+#include <vector>
+using namespace std;
+
+//P71.4
+//设单链表的表头指针为L, 结点结构由data和next两个域构成, 其中data域为字
+//符型。试设计算法判断该链表的全部n个字符是否中心对称。例如xyx、xyyx都是中
+//心对称
+
+#define ElemType int
+#define _for(i,a,b) for(int i=(a);i<(b);i++)
+#define INF 0x3f3f3f3f
+
+#pragma region 建立带头结点的链表
+
+typedef struct LNode {
+	ElemType data;
+	struct LNode* next;
+}LNode, * LinkList;
+
+//初始化链表
+bool InitList(LinkList& L) {
+	//分配一个头结点
+	L = (LNode*)malloc(sizeof(LNode));
+	//内存不足，分配失败
+	if (L == NULL) {
+		return false;
+	}
+	//头结点之后暂时还没有节点
+	L->next = NULL;
+	return true;
+}
+
+
+//判断是否为空
+bool IsEmpty(LinkList L) {
+	return ((L->next) == NULL);
+}
+
+//使用尾插法建表
+LinkList CreatList(vector<int> data) {
+	if (data.size() < 1) {
+		return NULL;
+	}
+	//头结点
+	LNode* head = (LinkList)malloc(sizeof(LNode));
+	head->data = NULL;
+	head->next = NULL;
+	LinkList p = head;
+	_for(i, 0, data.size()) {
+		LNode* s = (LinkList)malloc(sizeof(LNode));
+		s->data = data[i];
+		s->next = NULL;
+		p->next = s;
+		p = s;
+	}
+	return head;
+}
+//输出链表
+void PrintList(LinkList list) {
+	list = list->next;
+	while (list != NULL) {
+		printf("%d ", list->data);
+		list = list->next;
+	}
+	printf("\n");
+}
+
+#pragma endregion
+
+
+//P71.4
+bool Palindrome(LinkList L, int n) {
+	int* s = (int*)malloc(sizeof(int) * (n / 2));
+	LinkList p = L->next;
+	int count = 0;
+	for (count = 0; count < n / 2; count++) {
+		s[count] = p->data;
+		p = p->next;
+	}
+	count--;
+	if (n % 2 == 1)
+		p = p->next;
+
+	while (p && s[count] == p->data) {
+		count--;
+		p = p->next;
+	}
+	free(s);
+	if (count == -1)
+		return true;
+	return false;
+}
+
+
+int main()
+{
+	vector<int> data{ 1,2,3,4,4,3,2,1 };
+	LinkList head;
+	InitList(head);
+	head = CreatList(data);
+	PrintList(head);
+	cout << Palindrome(head,data.size());
+	return 0;
+}

栈和队列/栈/P71.5.cpp

@@ -0,0 +1,93 @@
+#include <iostream>
+#include <vector>
+using namespace std;
+
+#define MaxSize 5
+#define ElemType int
+
+
+#pragma region P71.5建立共享顺序栈
+
+typedef struct {
+	ElemType data[MaxSize];
+	int top[2];
+}SqStack;
+
+void InitStack(SqStack &S) {
+	S.top[0] = -1;
+	S.top[1] = MaxSize - 1;
+}
+ 
+bool Push(SqStack& S, ElemType x,int i) {
+	if (S.top[1] - S.top[0] == 1) {
+		cout << "栈以满！" << endl;
+		return false;
+	}
+	switch (i)
+	{
+		case 0: {
+			S.data[++S.top[0]] = x;
+			return true;
+		}
+		case 1: {
+			S.data[--S.top[1]] = x; 
+			return true;
+		}
+		default: {
+			cout << "入栈序号错误!" << endl; 
+			return false;
+		}
+	}
+}
+
+bool Pop(SqStack& S, ElemType& x,int i) {
+	switch (i)
+	{
+		case 0: {
+			if (S.top[0] == -1) {
+				cout << "0号栈为空！" << endl;
+				return false;
+			}
+			x = S.data[S.top[0]--];
+			return true;
+		}
+		case 1: {
+			if (S.top[1] == MaxSize-1) {
+				cout << "1号栈为空！" << endl;
+				return false;
+			}
+			x = S.data[S.top[1]++];
+			return true;
+		}
+		default: {
+			cout << "入栈序号错误!" << endl; 
+			return false;
+		}
+	}
+}
+
+#pragma endregion
+
+
+
+int main()
+{
+	//test
+	SqStack S;
+	InitStack(S);
+	Push(S, 2, 0);
+	Push(S, 1, 0);
+	Push(S, 4, 1);
+	Push(S, 3, 1);
+	int x;
+	Pop(S, x, 0);
+	cout << x << endl;
+	Pop(S, x, 0);
+	cout << x << endl;
+	Pop(S, x, 1);
+	cout << x << endl;
+	Pop(S, x, 1);
+	cout << x << endl;
+	return 0;
+}
+

栈和队列/队列/P85.1.cpp

@@ -0,0 +1,77 @@
+#include <iostream>
+#include <vector>
+using namespace std;
+
+//P85.1
+//若希望循环队列中的元素都能得到利用, 则需设置一个标志域tag, 并以tag的值为0
+//或1来区分队头指针 front和队尾指针rear相同时的队列状态是“空”还是“满”。试
+//编写与此结构相应的入队和出队算法
+#define ElemType int
+#define _for(i,a,b) for(int i=(a);i<(b);i++)
+#define INF 0x3f3f3f3f
+#define MaxSize 3
+
+#pragma region 建立循环队列
+
+typedef struct {
+	ElemType data[MaxSize];
+	int front, rear;
+	int tag;
+}SqQueue;
+
+
+//初始化链表
+void InitList(SqQueue& Q) {
+	Q.front = Q.rear = 0;
+}
+
+bool EnQueue(SqQueue& Q, ElemType x) {
+	if (Q.front == Q.rear && Q.tag == 1) {
+		cout << "full!" << endl;
+		return false;
+	}
+	Q.data[Q.rear] = x;
+	Q.rear = (Q.rear + 1) % MaxSize;
+	Q.tag = 1;
+	return true;
+}
+
+bool DeQueue(SqQueue& Q, ElemType& x) {
+	if (Q.front == Q.rear && Q.tag == 0) {
+		cout << "enpty" << endl;
+		return false;
+	}
+	x = Q.data[Q.front];
+	Q.front = (Q.front + 1) % MaxSize;
+	Q.tag = 0;
+	return true;
+}
+
+
+#pragma endregion
+
+
+
+
+int main()
+{
+	SqQueue Q;
+	InitList(Q);
+	EnQueue(Q, 1);
+	EnQueue(Q, 2);
+	EnQueue(Q, 3);
+	EnQueue(Q, 4);
+	int x;
+	DeQueue(Q, x);
+	cout << x << endl;
+
+	DeQueue(Q, x);
+	cout << x << endl;
+
+	DeQueue(Q, x);
+	cout << x << endl;
+
+	DeQueue(Q, x);
+	cout << x << endl;
+	return 0;
+}

栈和队列/队列/P85.2.cpp

@@ -0,0 +1,33 @@
+#include <iostream>
+#include <stack>
+#include <queue>
+
+using namespace std;
+
+//P85.2
+//Q是一个队列, S是一个空栈, 实现将队列中的元素逆置的算法
+
+//P85.2
+void Reserve(stack<int>& S, queue<int>& Q) {
+    while (!S.empty()) {
+        int x = S.top();
+        S.pop();
+        Q.push(x);
+    }
+
+}
+int main()
+{
+    stack<int> S;
+    queue<int> Q;
+    for (int i = 1; i <= 5; i++) {
+        S.push(i);
+    }
+    Reserve(S, Q);
+    for (int i = 1; i <= 5; i++) {
+        int x = Q.front();
+        Q.pop();
+        cout << x << endl;
+    }
+    return 0;
+}