diff --git a/czxt.txt b/czxt.txt
new file mode 100644
index 00000000..dcd4370a
--- /dev/null
+++ b/czxt.txt
@@ -0,0 +1,396 @@
+实验五存储管理
+#include <stdio.h>
+#include <stdlib.h>
+#include <malloc.h>
+#include <time.h>
+#define LEN sizeof(MEMORY_BLOCK)
+#define NUM 5
+struct MEMORY_BLOCK
+{
+	int name;
+	int address;
+	int length;
+	int flag;
+	struct MEMORY_BLOCK *next;
+};
+typedef struct MEMORY_BLOCK MEMORY_BLOCK;
+void allocation(MEMORY_BLOCK *Header,int name,int length_p);
+void reclaim(int processname, MEMORY_BLOCK *Header);
+void main()
+{
+
+	int length_p,i;
+	int processname;
+	MEMORY_BLOCK *Header,*t;
+	Header=(MEMORY_BLOCK*)malloc(LEN);//初始化存储空间
+	Header->name=-1;
+	Header->address=0;
+	Header->length=100;
+	Header->flag=0;
+	Header->next=NULL;
+	srand((int)time(0));
+	for(i=1;i<=NUM;i++)
+	{
+		length_p=rand()%20+1;   //随机产生进程所需存储空间，至少为1;
+		allocation(Header,i,length_p);
+	}
+
+	printf("内存分配情况:  \n");
+	t=Header;
+	while(t!=NULL)
+	{
+		printf("process name %d, address=%d, length=%d,flag=%d\n",t->name,t->address,t->length,t->flag);
+		t=t->next;
+	}
+
+	printf("请输入回收的进程号(输入0结束):\n");
+	scanf("%d",&processname);	
+	while(processname!=0)
+	{
+
+		printf("回收 process name %d\n",processname);
+		reclaim(processname,Header);
+		t=Header;
+		while(t!=0)
+		{
+			printf("process name %d, address=%d, length=%d,flag=%d\n",t->name,t->address,t->length,t->flag);
+			t=t->next;
+		}
+		if (Header->next==NULL) break;
+		printf("请输入回收的进程号(输入0结束):\n");
+		scanf("%d",&processname);
+	}
+	
+	
+	printf("当前内存分配情况：\n");
+	t=Header;
+	while(t!=0)
+	{
+		printf("process name %d, address=%d, length=%d,flag=%d\n",t->name,t->address,t->length,t->flag);
+		t=t->next;
+	}
+}
+
+void reclaim(int processname, MEMORY_BLOCK *Header)
+{
+	MEMORY_BLOCK *temp,*t,*tt;
+	t=Header;
+	temp=t;
+	while(t->name!=processname)
+	{
+		temp=t;
+		t=t->next;
+	} 
+	if(t->next!=NULL)//t非尾结点
+		if(temp->flag==0&&t->next->flag==0)//左右为空
+		{
+			temp->name=-1;
+			temp->length=temp->length+t->length+t->next->length;
+			tt=t->next;
+			temp->next=tt->next;
+		}
+		else if(temp->flag==0) //左为空
+		{
+			temp->name=-1;
+			temp->length=temp->length+t->length;
+			temp->next=t->next;
+		}
+			else if(t->next->flag==0) //右为空
+			{
+            t->length=t->length+t->next->length;
+            tt=t->next;
+            t->next=tt->next;
+			}
+				else //	左右不为空
+				{
+					t->name=-1;
+                    t->flag=0
+				}
+	else//t是尾结点
+	{
+		if(temp->flag==0) //左为空
+ 		{
+			temp->length = temp->length + t->length;
+            temp->next = NULL;
+            free(t);
+		}
+		else //	左不为空
+		{
+        t->name=-1;
+        t->flag=0;
+		}
+	}
+}
+
+void allocation(MEMORY_BLOCK *Header,int name,int length_p)
+{
+	MEMORY_BLOCK *temp,*t,*tt;
+	int minsize=2; //不可切割的分区阈值
+	t=Header;
+	while(t!=0)
+	{
+		if(t->length>length_p&&t->flag==0) break;
+		t=t->next;
+	}
+	if(t->length-length_p>minsize) //分割
+	{
+		temp=(MEMORY_BLOCK*)malloc(LEN);//temp=new MEMORY_BLOCK;
+		temp->name=-1;
+		temp->flag=0;
+		temp->length=t->length-length_p;
+		temp->address=t->address+length_p;
+		t->name=name;
+		t->flag=1;
+		t->length=length_p;
+		temp->next=t->next;
+		t->next=temp;
+	}
+	else  //直接分配
+	{
+    t->name=name;
+    t->flag=1     
+	}	
+}
+
+实验三进程调度
+#include <stdio.h>
+#include <stdlib.h>
+#include <malloc.h>
+#include <time.h>
+#define NUM 8
+#define LEN sizeof(PCB)
+struct PCB
+{
+	int name;
+	int runtime;
+    int runedtime;
+	int killtime;
+   struct PCB *next;
+};
+typedef struct PCB PCB;
+
+
+
+void main()
+{
+   int timeslice=5;
+   PCB *runqueue;
+   PCB *top,*tail,*temp;
+   int i;
+   srand((int)time(0));
+   for(i=0;i<NUM;i++)
+   { 
+     temp=(PCB*)malloc(LEN);
+     temp->name=i;
+     temp->runtime=rand()%15+1;
+     temp->runedtime=0;
+     temp->killtime=0;
+     temp->next=NULL;
+     if(i==0) 
+     {
+       top=temp; 
+       tail=temp;
+     }
+     else
+     {
+       tail->next=temp;
+       tail=temp;
+     }
+     printf("START:process name %d, runtime=%d, runedtime=%d,killtime=%d\n",tail->name,tail->runtime,tail->runedtime,tail->killtime); 
+   }
+   printf("******************************\n");
+   while(top!=NULL)
+   { 
+      runqueue=top;
+      top=top->next;
+      runqueue->next=NULL;
+      runqueue->runtime=runqueue->runtime-timeslice;
+      if(runqueue->runtime<=0)
+      {
+        runqueue->killtime=runqueue->killtime+timeslice;
+        runqueue->runedtime=runqueue->runedtime+runqueue->killtime;
+        runqueue->runtime=0;
+        printf("process name %d, runtime=%d, runedtime=%d,killtime=%d...END...\n",runqueue->name,runqueue->runtime,runqueue->runedtime,runqueue->killtime);
+      }
+     else
+      {
+        runqueue->runedtime += timeslice;
+        runqueue->runtime -= timeslice;
+        printf("process name %d, runtime=%d, runedtime=%d,killtime=%d\n",runqueue->name,runqueue->runtime,runqueue->runedtime,runqueue->killtime);
+        if (tail != NULL) 
+        {
+          tail->next = runqueue;
+        } else {
+          top = runqueue;
+        }
+        tail = runqueue;
+     }
+   }
+}
+
+实验二进程控制下
+
+#include<stdlib.h>
+#include<unistd.h>
+#include<sys/types.h>
+#include<sys/wait.h>
+#include<stdio.h>
+int main()
+{  
+  int fpid,fpid2,cpid1,cpid2;
+  int status,i,j;
+  fpid=fork();
+  if(fpid<0)
+  {
+	perror("fork failed\n");
+	exit(0);
+  }
+  else if(fpid==0)
+  {
+		printf("I am son, my PID is %d, parent PID is %d\n",
+               getpid(),getppid());  
+		printf("I am working\n");
+		sleep(1);
+        printf("I am done\n");
+		exit(4);
+	
+  }
+  else if (fpid>0) 
+    {
+    /* 创建第二个子进程（女儿） */
+        fpid2=fork();
+        if (fpid2==0) 
+        {
+        // 女儿进程执行代码
+            printf("I am daughter, my PID is %d, parent PID is %d\n",
+              getpid(),getppid());
+            printf("I am working\n");
+            sleep(1);
+            printf("I am finished\n");
+            exit(5);
+        } 
+        else if (fpid2<0) 
+        {
+            perror("Second fork failed");
+            return 1;
+        }
+        else if(fpid2>0)
+        {/* 父进程执行代码 */
+            printf("I am father, my PID is %d, son PID is %d, daughter PID is %d\n",
+            getpid(),fpid,fpid2);  
+                              //WEXITSTATUS(status)可以得到调用程序的返回值
+             cpid1=wait(&status);
+         if(WIFEXITED(status))
+         i=WEXITSTATUS(status);
+          cpid2=wait(&status);
+         if(WIFEXITED(status))
+         j=WEXITSTATUS(status);
+            printf("Child %d exited with status %d\n",cpid1,i);
+            printf("Child %d exited with status %d\n", cpid2,j);
+
+        }
+   
+    }   
+}
+
+实验二上1
+#include<stdlib.h> 
+#include<unistd.h>
+#include<stdio.h>
+#include <sys/wait.h>
+#include <stdlib.h>
+//-------begin---------
+
+
+int main() {
+    pid_t son_pid, daughter_pid;
+
+    
+    son_pid = fork();
+    if (son_pid == 0) {
+       
+        printf("I am son, my pid is %d, parent pid is %d\n", getpid(), getppid());
+        exit(0);
+    } else if (son_pid < 0) {
+        perror("fork failed");
+        exit(1);
+    }
+
+    daughter_pid = fork();
+    if (daughter_pid == 0) {
+       
+        printf("I am daughter, my pid is %d, parent pid is %d\n", getpid(), getppid());
+        exit(0);
+    } else if (daughter_pid < 0) {
+        perror("fork failed");
+        exit(1);
+    }
+
+    
+    if (son_pid > 0 || daughter_pid > 0) {
+        printf("I am father, my pid is %d, son's pid is %d, daughter's pid is %d\n", 
+               getpid(), son_pid, daughter_pid);
+        
+        
+    }
+
+    return 0;
+}
+
+
+2
+
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <stdlib.h>
+
+int main() {
+    pid_t son_pid, daughter_pid;
+
+    // 创建儿子进程
+    son_pid = fork();
+
+    if (son_pid < 0) {
+        // 创建子进程失败
+        perror("Fork for son failed");
+        return 1;
+    } else if (son_pid == 0) {
+        // 儿子进程
+        printf("I am son, my PID is %d, my father's PID is %d. Executing 'ls'...\n", getpid(), getppid());
+        fflush(stdout);
+        execlp("ls", "ls", NULL);
+        // 如果exec调用失败，会执行到这里
+        perror("execlp for ls failed");
+        exit(EXIT_FAILURE);
+    } else {
+        // 创建女儿进程
+        daughter_pid = fork();
+
+        if (daughter_pid < 0) {
+            // 创建子进程失败
+            perror("Fork for daughter failed");
+            return 1;
+        } else if (daughter_pid == 0) {
+            // 女儿进程
+            printf("I am daughter, my PID is %d, my father's PID is %d. Executing 'pwd'...\n", getpid(), getppid());
+            fflush(stdout);
+            execlp("pwd", "pwd", NULL);
+            // 如果exec调用失败，会执行到这里
+            perror("execlp for pwd failed");
+            exit(EXIT_FAILURE);
+        } else {
+            // 父进程
+            printf("I am father, my PID is %d, my son's PID is %d, my daughter's PID is %d\n", getpid(), son_pid, daughter_pid);
+            fflush(stdout);
+            // 等待儿子进程结束
+            waitpid(son_pid, NULL, 0);
+            // 等待女儿进程结束
+            waitpid(daughter_pid, NULL, 0);
+        }
+    }
+
+    return 0;
+}
+