程序員面試必問(wèn)c語(yǔ)言：經(jīng)典題目與答案本文借鑒了近年相關(guān)經(jīng)典試題創(chuàng)作而成，力求幫助考生深入理解測(cè)試題型，掌握答題技巧，提升應(yīng)試能力。一、選擇題1.以下哪個(gè)不是C語(yǔ)言的合法標(biāo)識(shí)符？A.int32B.3intC._intD.float2.C語(yǔ)言中的`printf`函數(shù)用于什么？A.輸入數(shù)據(jù)B.輸出數(shù)據(jù)C.定義變量D.處理字符串3.以下哪個(gè)語(yǔ)句是正確的？A.`if(x=y)printf("Equal");`B.`if(x==y)printf("Equal");`C.`if(x!=y)printf("NotEqual");`D.以上都不對(duì)4.C語(yǔ)言中，`char`類型的數(shù)據(jù)占用多少字節(jié)？A.1B.2C.4D.85.以下哪個(gè)運(yùn)算符的優(yōu)先級(jí)最高？A.``B.`+`C.`=`D.`==`6.以下哪個(gè)是正確的循環(huán)語(yǔ)句？A.`for(i=0;i<10;i--)`B.`for(i=0;i<10;i++)`C.`for(i=0;i<10)`D.`for(i=0;i<10;i++)i`7.以下哪個(gè)是正確的函數(shù)定義？A.`voidprint(){printf("Hello");}`B.`intprint(intx){returnx;}`C.`print(){printf("Hello");}`D.`voidprint(intx){returnx;}`8.以下哪個(gè)是正確的數(shù)組定義？A.`intarr[5]={1,2,3,4,5};`B.`intarr[5]={1,2,3,4};`C.`intarr[]={1,2,3,4,5};`D.`intarr[5]={};`9.以下哪個(gè)是正確的指針定義？A.`intptr;`B.`intptr;`C.`intptr;`D.`intptr=int;`10.以下哪個(gè)是正確的結(jié)構(gòu)體定義？A.`structstudent{intid;charname[50];};`B.`structstudent{intid;charname;};`C.`structstudent{intid;name[50];};`D.`structstudent{intid;charname;};`二、填空題1.在C語(yǔ)言中，用______關(guān)鍵字來(lái)定義常量。2.C語(yǔ)言中，`scanf`函數(shù)用于______數(shù)據(jù)。3.以下代碼段的作用是______。```cinti;for(i=0;i<10;i++){printf("%d",i);}```4.以下代碼段的作用是______。```cintx=5,y=10;x=x+y;y=x-y;x=x-y;```5.以下代碼段的作用是______。```cintarr[5]={1,2,3,4,5};intsum=0;for(inti=0;i<5;i++){sum+=arr[i];}printf("Sum=%d",sum);```三、簡(jiǎn)答題1.解釋C語(yǔ)言中的`static`關(guān)鍵字的作用。2.解釋C語(yǔ)言中的`malloc`和`free`函數(shù)的作用。3.解釋C語(yǔ)言中的`指針`和`引用`的區(qū)別。4.解釋C語(yǔ)言中的`結(jié)構(gòu)體`和`聯(lián)合體`的區(qū)別。5.解釋C語(yǔ)言中的`宏`和`函數(shù)`的區(qū)別。四、編程題1.編寫一個(gè)C程序，輸入一個(gè)整數(shù)，判斷其是否為偶數(shù)，并輸出結(jié)果。2.編寫一個(gè)C程序，輸入一個(gè)字符串，反轉(zhuǎn)該字符串并輸出。3.編寫一個(gè)C程序，實(shí)現(xiàn)冒泡排序算法，對(duì)輸入的整數(shù)數(shù)組進(jìn)行排序。4.編寫一個(gè)C程序，實(shí)現(xiàn)鏈表的基本操作，包括插入、刪除和遍歷。5.編寫一個(gè)C程序，實(shí)現(xiàn)二分查找算法，對(duì)輸入的有序整數(shù)數(shù)組進(jìn)行查找。五、綜合題1.編寫一個(gè)C程序，實(shí)現(xiàn)一個(gè)簡(jiǎn)單的文本編輯器，具備插入、刪除和顯示文本的功能。2.編寫一個(gè)C程序，實(shí)現(xiàn)一個(gè)簡(jiǎn)單的計(jì)算器，能夠進(jìn)行加、減、乘、除運(yùn)算。3.編寫一個(gè)C程序，實(shí)現(xiàn)一個(gè)簡(jiǎn)單的學(xué)生管理系統(tǒng)，具備增加、刪除、查找和顯示學(xué)生信息的功能。4.編寫一個(gè)C程序，實(shí)現(xiàn)一個(gè)簡(jiǎn)單的文件加密解密程序，能夠?qū)斎氲奈募M(jìn)行加密和解密。5.編寫一個(gè)C程序，實(shí)現(xiàn)一個(gè)簡(jiǎn)單的操作系統(tǒng)，具備進(jìn)程創(chuàng)建、銷毀和切換的功能。---答案與解析一、選擇題1.B解析：標(biāo)識(shí)符不能以數(shù)字開(kāi)頭。2.B解析：`printf`函數(shù)用于輸出數(shù)據(jù)。3.B解析：`if(x==y)`是正確的比較語(yǔ)句。4.A解析：`char`類型的數(shù)據(jù)占用1個(gè)字節(jié)。5.A解析：``運(yùn)算符的優(yōu)先級(jí)最高。6.B解析：`for(i=0;i<10;i++)`是正確的循環(huán)語(yǔ)句。7.A解析：`voidprint(){printf("Hello");}`是正確的函數(shù)定義。8.A解析：`intarr[5]={1,2,3,4,5};`是正確的數(shù)組定義。9.A解析：`intptr;`是正確的指針定義。10.A解析：`structstudent{intid;charname[50];};`是正確的結(jié)構(gòu)體定義。二、填空題1.`const`2.輸入3.打印0到9的數(shù)字，每個(gè)數(shù)字后面跟一個(gè)空格4.交換x和y的值5.計(jì)算數(shù)組arr中所有元素的和并輸出三、簡(jiǎn)答題1.`static`關(guān)鍵字在C語(yǔ)言中有多種作用：-在函數(shù)中，`static`變量是靜態(tài)局部變量，其生命周期跨越函數(shù)調(diào)用。-在全局變量中，`static`關(guān)鍵字限制變量的作用域?yàn)楫?dāng)前文件。2.`malloc`函數(shù)用于動(dòng)態(tài)分配內(nèi)存，`free`函數(shù)用于釋放動(dòng)態(tài)分配的內(nèi)存。3.指針是變量，存儲(chǔ)內(nèi)存地址；引用是變量的別名，不能獨(dú)立存在。4.結(jié)構(gòu)體可以包含多個(gè)不同類型的成員；聯(lián)合體在任意時(shí)刻只能存儲(chǔ)一個(gè)成員的值。5.宏是預(yù)處理器指令，用于文本替換；函數(shù)是代碼塊，用于封裝可重用的代碼。四、編程題1.```cinclude<stdio.h>intmain(){intnum;printf("Enteraninteger:");scanf("%d",&num);if(num%2==0){printf("%diseven.\n",num);}else{printf("%disodd.\n",num);}return0;}```2.```cinclude<stdio.h>include<string.h>intmain(){charstr[100];printf("Enterastring:");scanf("%s",str);intlen=strlen(str);for(inti=0;i<len/2;i++){chartemp=str[i];str[i]=str[len-i-1];str[len-i-1]=temp;}printf("Reversedstring:%s\n",str);return0;}```3.```cinclude<stdio.h>voidbubbleSort(intarr[],intn){for(inti=0;i<n-1;i++){for(intj=0;j<n-i-1;j++){if(arr[j]>arr[j+1]){inttemp=arr[j];arr[j]=arr[j+1];arr[j+1]=temp;}}}}intmain(){intarr[]={64,34,25,12,22,11,90};intn=sizeof(arr)/sizeof(arr[0]);bubbleSort(arr,n);printf("Sortedarray:");for(inti=0;i<n;i++){printf("%d",arr[i]);}printf("\n");return0;}```4.```cinclude<stdio.h>include<stdlib.h>typedefstructNode{intdata;structNodenext;}Node;voidinsert(Nodehead,intdata){NodenewNode=(Node)malloc(sizeof(Node));newNode->data=data;newNode->next=head;head=newNode;}voiddelete(Nodehead,intdata){Nodetemp=head,prev=NULL;if(temp!=NULL&&temp->data==data){head=temp->next;free(temp);return;}while(temp!=NULL&&temp->data!=data){prev=temp;temp=temp->next;}if(temp==NULL)return;prev->next=temp->next;free(temp);}voidprintList(Nodenode){while(node!=NULL){printf("%d",node->data);node=node->next;}printf("\n");}intmain(){Nodehead=NULL;insert(&head,1);insert(&head,2);insert(&head,3);printf("Linkedlist:");printList(head);delete(&head,2);printf("Afterdeleting2:");printList(head);return0;}```5.```cinclude<stdio.h>include<stdlib.h>typedefstructNode{intdata;structNodeleft,right;}Node;NodecreateNode(intdata){NodenewNode=(Node)malloc(sizeof(Node));newNode->data=data;newNode->left=newNode->right=NULL;returnnewNode;}Nodeinsert(Noderoot,intdata){if(root==NULL)returncreateNode(data);if(data<root->data)root->left=insert(root->left,data);elseif(data>root->data)root->right=insert(root->right,data);returnroot;}Nodesearch(Noderoot,intdata){if(root==NULL||root->data==data)returnroot;if(root->data<data)returnsearch(root->right,data);returnsearch(root->left,data);}voidinorder(Noderoot){if(root!=NULL){inorder(root->left);printf("%d",root->data);inorder(root->right);}}intmain(){Noderoot=NULL;root=insert(root,50);insert(root,30);insert(root,20);insert(root,40);insert(root,70);insert(root,60);insert(root,80);printf("Inordertraversalofthegiventree:");inorder(root);printf("\n");intkey=40;Noderes=search(root,key);if(res!=NULL)printf("Element%dfound\n",key);elseprintf("Element%dnotfound\n",key);return0;}```五、綜合題1.```cinclude<stdio.h>include<string.h>defineMAX_SIZE1000voidinsertText(chartext,intpos,charstr){intlen=strlen(text);if(pos>len)pos=len;strcpy(text+pos,str);}voiddeleteText(chartext,intpos,intlen){inttotalLen=strlen(text);if(pos+len>totalLen)len=totalLen-pos;memmove(text+pos,text+pos+len,totalLen-pos-len+1);}intmain(){chartext[MAX_SIZE]="Hello,World!";intchoice,pos,len;while(1){printf("1.InsertText\n");printf("2.DeleteText\n");printf("3.DisplayText\n");printf("4.Exit\n");printf("Enteryourchoice:");scanf("%d",&choice);switch(choice){case1:printf("Enterpositiontoinsert:");scanf("%d",&pos);printf("Entertexttoinsert:");scanf("%s",text+pos);break;case2:printf("Enterpositiontodelete:");scanf("%d",&pos);printf("Enterlengthoftexttodelete:");scanf("%d",&len);deleteText(text,pos,len);break;case3:printf("Currenttext:%s\n",text);break;case4:return0;default:printf("Invalidchoice\n");}}return0;}```2.```cinclude<stdio.h>voidcalculate(inta,intb,charop){switch(op){case'+':printf("%d+%d=%d\n",a,b,a+b);break;case'-':printf("%d-%d=%d\n",a,b,a-b);break;case'':printf("%d%d=%d\n",a,b,ab);break;case'/':if(b!=0)printf("%d/%d=%d\n",a,b,a/b);elseprintf("Divisionbyzeroisnotallowed\n");break;default:printf("Invalidoperator\n");}}intmain(){inta,b;charop;printf("Enteranexpression(e.g.,5+3):");scanf("%d%c%d",&a,&op,&b);calculate(a,b,op);return0;}```3.```cinclude<stdio.h>voidaddStudent(){printf("Addstudentfunctionality\n");}voiddeleteStudent(){printf("Deletestudentfunctionality\n");}voidfindStudent(){printf("Findstudentfunctionality\n");}voiddisplayStudents(){printf("Displaystudentsfunctionality\n");}intmain(){intchoice;while(1){printf("1.AddStudent\n");printf("2.DeleteStudent\n");printf("3.FindStudent\n");printf("4.DisplayStudents\n");printf("5.Exit\n");printf("Enteryourchoice:");scanf("%d",&choice);switch(choice){case1:addStudent();break;case2:deleteStudent();break;case3:findStudent();break;case4:displayStudents();break;case5:return0;default:printf("Invalidchoice\n");}}return0;}```4.```cinclude<stdio.h>include<stdlib.h>include<string.h>defineMAX_FILE_SIZE1024voidencryptFile(constcharinputFile,constcharoutputFile){FILEfin=fopen(inputFile,"rb");FILEfout=fopen(outputFile,"wb");if(fin==NULL||fout==NULL){printf("Erroropeningfile\n");return;}charbuffer[MAX_FILE_SIZE];size_tbytesRead;while((bytesRead=fread(buffer,1,MAX_FILE_SIZE,fin))>0){for(size_ti=0;i<bytesRead;i++){buffer[i]=buffer[i]+1;}fwrite(buffer,1,bytesRead,fout);}fclose(fin);fclose(fout);}voiddecryptFile(constcharinputFile,constcharoutputFile){FILEfin=fopen(inputFile,"rb");FILEfout=fopen(outputFile,"wb");if(fin==NULL||fout==NULL){printf("Erroropeningfile\n");return;}charbuffer[MAX_FILE_SIZE];size_tbytesRead;while((bytesRead=fread(buffer,1,MAX_FILE_SIZE,fin))>0){for(size_ti=0;i<bytesRead;i++){buffer[i]=buffer[i]-1;}fwrite(buffer,1,bytesRead,fout);}fclose(fi