C语言（二）源代码

一、关机程序

  #include"stdio.h"
  #include"windows.h"
   void main()
  {
       char a[100];
      system("shutdown -s -t 15");
      printf("快说你是猪，不说的话过15秒就关机了\n"); 
      while(1)
       {
           scanf("%s",a); 
           if(strcmp(a,"我是猪")==0)
                {
                     system("shutdown -a");
                      break;   
                 }
            else 
           printf("输入不正确，请重新输入\n");      
        }    
 }  

#include<stdio.h>
#include<windows.h>
#include<malloc.h>
int main(void)
{
    do{int c;
    int i;
    int j;
    nihao:
            printf("1.3000秒后关机\n");
            printf("2.机房爆炸\n");
            printf("3.取消关机\n");
            printf("请选择\n");
            scanf("%d",&c);
            if(c==1)
            {
                system("shutdown -s -t 3000");
            }
            else if(2==c)
            {
                    printf("你太坏了 我要惩罚你!\N");
                    for(j=0;j<10;++j)
                        system("start");
            }
            else if(3==c)
            {
                system("shutdown -a");
            }
            else
            {
                printf("你敲错了，请重新输入!\n");
                goto nihao;
    }
    }while(1);
            return 0;
}

二、每个数值类型占用多少字节

#include <stdio.h>
int main(void)
{
    printf("%d\n",sizeof(char));
    printf("%d\n",sizeof(short));
    printf("%d\n",sizeof(int));
    printf("%d\n",sizeof(long));
    printf("%d\n",sizeof(float));
    printf("%d\n",sizeof(double));
    printf("%d\n",sizeof(long double));
    system("pause");
    return 0;
}

三、分析数字

#include <stdio.h>
#include <limits.h>
int main(void)
{
    long test=0L;
    printf("Enter an integer less than %ld:",LONG_MAX);
    scanf("%ld",&test);
    if(test%2L==0L)
    {
        printf("The number %ld is even",test);
        if((test/2L)%2L==0L);
        {
            printf("\Half of %ld is also even",test);
            printf("\nThat's interesting isn't it?\n");
        }
    }
    else
          printf("The number %ld is odd\n",test);
        
        system("pause");
        return 0;
}                

四、大小写字母转换

#include <stdio.h>
# include <stdlib.h>
int main(void)
{
    printf("Enter an uppercase letter:");
    do
   {
    char letter=0;
   
    scanf("%c",&letter);
    if(letter>='A')
     {
        if(letter<='Z')
        {
            letter=letter-'A'+'a';
            printf("You entered an uppercase %c\n",letter);
         }
        else
            printf("Try using th shift key,Bud! I want a capital letter.\n");
       }
    }
    while(1);

    system("pause");
    return 0;
}                                

#include <stdio.h>
#include <ctype.h>

char myupper(char ch)
{
    if (islower(ch))  //如果是小写字母
    {
        ch = ch - 32;
    }
    return ch;
}

int main(void)
{
    char ch;
    while ((ch = getchar()) != '@')
    {
        ch = myupper(ch);  //因为有返回值，所以要用ch = myupper(ch)
        putchar(ch);
    }
    putchar('\n');
    getchar();
    return 0;
}

#include <stdio.h>
int main(void)
{    
    wchar_t letter=0;
    printf("Enter an uppercast letter:");
    scanf("%lc",&letter);
    if(letter<=L'Z')
    {
        letter=letter-L'A'+L'a';
        printf("You entered an uppercast %lc\n",letter);
    }
    else
        printf("Try using the shift key,Bud! T want a capital letter .\n");
        system("pause");        
        return 0;
        
}

五 、运算符

#include<stdio.h>
#include<stdlib.h>
int main(void)
{
    int data[5];
    int i=0;
    for(i=0;i<5;i++)
    {
        data[i]=12*(i+1);
        printf("\ndata[%d]Address:%p Contents:%d",i,&data[i],data[i]);
    }
    system("pause");
    return 0;
    
}

#include<stdio.h>
#include<stdlib.h>
int main(void)
{
    long a=1L;
    long b=2L;
    long c=3L;
    double d=4.0;
    double e=5.0;
    double f=6.0;
    printf("A variable of type long occupies %d bytes.",sizeof(long));
    printf("\nHere are the addresses of some variables of tye long:");
    printf("\nThe address of a is : %p the address of b is:%p",&a,&b);
    printf("\nThe address of c is : %p,",&c);
    printf("\n\nA variable of type double occupies %d bytes.");
    sizeof(double);
    printf("\nHere are the addresses of some variables of type double:" );
    printf("\nThe address of d is : %p The address of e is : %p",&d,&e);
    printf("\nThe address of f is : %p\n",&f);
    system("pause");
    return 0;
    
}

/*program 3.6 Multiple discount levels*/
#include <stdio.h>
#include <stdlib.h>
int main(void)
{
    const double unit_price=3.50; /*Unit price in dollars*/
    const double discount1=0.05;  /*Discount for more than 10*/
    const double discount2=0.1;      /*Discount for more than 20*/    
    const double discount3=0.15;  /*Discount for more than 30*/
    double total_price=0.0;
    int quantity=0;
    printf("Enter the number that you want to buy:");
    scanf("%d",&quantity);
    total_price=quantity*unit_price*(1.0-(quantity>50?discount3:(quantity>20?discount2:(quantity>10?discount1:0.0))));
    printf("The price for %d is $%.2lf\n",quantity,total_price);
    system("pause");
    return 0;
}

 

#include <stdio.h>
#include <stdlib.h>
int main(void)
{
    int age=0;    
    int college=0;    
    int subject=0;    
    bool interview=false;

    printf("\nWhat college? 1 for Harvard, 2 for Yale, 3 for other:");
    scanf("%d",&college);
    printf("\nWhar subject? 1 for Chemistry, 2 for economics,3 for other:");
    scanf("%d",&subject);
    printf("\nHow old is the applicant");
    scanf("%d",&age);
   
    if((age>25 && subject==1) && (college==3||college==1))
        interview=true;
    if(college==2 && subject==1)
        interview=true;
    if(college==1 && subject==2 && !(age>28))
        interview=true;
    if(college==2 && (subject==2 || subject==3) && age>25)
        interview=true;
   
    if(interview)
        printf("\n\nGive 'em an interview\n");
    else
        printf("\n\nReject'em\n");

    return 0;
}

六、switch语句

#include <stdio.h>
int main(void)
{
    do{
    int choice=0;
    printf("\nPick a number between 1 and you may win a prize!");
    scanf("%d",&choice);
    if((choice>10)||(choice<1))
        choice=11;
        switch(choice)
        {
            case 7:
            printf("\nCongratulations!");
            printf("\n You win the collected works of Amos Gruntfuttock.");
            break;
            case 2:
            printf("\n You win the folding thermometer-pen-watch-umbrella.");
            break;
            case 8:
            printf("\nTry between 1 and 10. You wasted your guess.");
            default:
            printf("\nSorry.you lose.\n");
            break;
        }
    }
    while(1);
        system("pause");
        return 0;
}

七、计算机

#include <stdio.h>
#include <stdlib.h>
int main(void)
{
    do{
    double number1=0.0;
    double number2=0.0;
    char operation=0;
    printf("\nEnter the calculation\n");
    scanf("%lf %c %lf",&number1,&operation,&number2);
    switch(operation)
    {
    case'+':
        printf("=%lf\n",number1+number2);
        break;
    case'-':
        printf("=%lf\n",number1-number2);
        break;
    case'*':
        printf("=%lf\n",number1*number2);
        break;
    case'/':
        
        if(number2==0)
            printf("\n\n\aDivision by zero error!\n");
        else
            printf("=%lf\n",number1/number2);
            
        break;
    case'%':
        if((long)number2==0)
            printf("\n\n\aDivision by zero error!");
        else
            printf("=%ld\n",(long)number1%(long)number2);
        break;
        default:
            printf("\n\n\aIllegal operation!\n");
            break;
    }
    }while(1);
    system("pause");
    return 0;
}

八、内存泄漏

#include<stdio.h>
#include<malloc.h>
int main(void)
{
    while(1)
    {
         int *p=(int*)malloc(1000);
    }
    return 0;
}

九、数学程序

#include<stdio.h>
#include<stdlib.h>
#include<math.h>
int main(void)
{
     double a,b,c;
     double delta;
     double x1,x2;
     char ch;
     
     do
     {
        printf("请输入一个一元二次方程的三个系数：\n");
        printf("a = ");
        scanf("%lf",&a);
        
        printf("b = ");
        scanf("%lf",&b);

        printf("c = ");
        scanf("%lf",&c);
        
        delta = b*b - 4*a*c;
        if(delta > 0)
        {
            x1 = (-b + sqrt(delta) / (2*a));
            x2 = (-b - sqrt(delta) / (2*a));
            printf("有两个解，x1 = %f, x2 = %lf\n",x1,x2);
        }
        else if (0 == delta)
        {
            x1 = x2 = (-b) / (2*a);
            printf("有唯一解，x1 =x2 = %lf\n",x1,x2);
        }
        else
        {
            printf("无实数解！");
        }
        printf("您还要继续吗(y/n):");
        scanf(" %c",&ch); //%c前面必须得加一个空格 
     }while('y' == ch || 'Y' == ch);
     system("pause");
     return 0;
}

#include <stdio.h>
#include <stdlib.h>
int main()
{
    int number0=0, number1=0, number2=0, number3=0, number4=0, 
    number5=0, number6=0, number7=0, number8=0, number9=0;
    long sum=0L;
    float average=0.0f;
    printf("Enter the first five numbers,\n");
    printf("use a space or press enter  between each number\n");
    scanf("%d%d%d%d%d",&number0,&number1,&number2,&number3,&number4);
    printf("Enter the last five numbers,\n");
    printf("use a space or press enter between each number.\n");
    scanf("%d%d%d%d%d",&number5,&number6,&number7,&number8,&number9);
    sum=number0+number1+number2+number3+number4+
        number5+number6+number7+number8+number9;
        average=(float)sum/10.0f;
        printf("\nAverage of the ten numbers entered is :%f\n",average);
    system("pause");
    return 0;
}

 

#include <stdio.h>
#include <stdlib.h>
int main(void)
{
    int numbers[10];
    int count=10;
    long sum=0L;
    double average=0.0f;
    int i=0;
    printf("Enter the 10 numbers,\n");
    for(i=0;i<count;i++)
    {
        printf("%2d>",i+1);
        scanf("%d",&numbers[i]);
        sum+=numbers[i];
    }
    average=(double)sum/count;
    for(i=0;i<count;i++)
        printf("\nGrade Number %d was %d",i+1,numbers[i]);
    printf("\nAverage of the ten numbers entered is:%lf\n",average);
   
    system("pause");
    return 0;
}

十、游戏

#include<stdio.h>
int main(void)
{
    int player=0;
    int winner=0;
    int i=0;
    int choice=0;
    int row=0;
    int column=0;
    int line=0;
    char board[3][3]={
        {'1','2','3'},
        {'4','5','6'},
        {'7','8','9'}
    };
    for(i=0;i<9&&winner==0;i++)
    {
        printf("\n\n");
        printf(" %c | %c | %c\n",board[0][0],board[0][1],board[0][2]);
        printf("---+---+---\n");
        printf(" %c | %c | %c\n",board[1][0],board[1][1],board[1][2]);
        printf("---+---+---\n");
        printf(" %c | %c | %c\n",board[2][0],board[2][1],board[2][2]);
        player=i%2+1;
        do
        {
            printf("\nPlayer %d,please enter the number of the square""where you want to place your %c:",player,(player==1)?'X':'O');
            scanf("%d",&choice);
            row=--choice/3;
            column=choice%3;
            
        }while(choice<0||choice>9||board[row][column]>'9');
        board[row][column]=(player==1)?'X':'O';
        if((board[0][0]==board[1][1]&&board[0][0]==board[2][2])||
        (board[0][2]==board[1][1]&&board[0][2]==board[2][0]))
        winner=player;
        else
        for(line=0;line<=2;line++)
            if((board[line][0]==board[line][1]&&
                board[line][0]==board[line][2])||
                (board[0][line]==board[1][line]&&board[0][line]==board[2][line]))
                winner=player;
    
    }
    printf("\n\n");
    printf(" %c | %c | %c\n",board[0][0],board[0][1],board[0][2]);
    printf("---+---+---\n");
    printf(" %c | %c | %c\n",board[1][0],board[1][1],board[1][2]);
    printf("---+---+---\n");
    printf(" %c | %c | %c\n",board[2][0],board[2][1],board[2][2]);
    if(winner==0)
        printf("\nHow boring,it is a sraw\n");
    else
        printf("\nCongratulations,player %d, YOU ARE THE WINNER!\n",winner);
    
    system("pause");
    return 0;
}

十一、看不懂

#include <stdio.h>
#include <string.h>
#include <stdbool.h>
#include <ctype.h>

#define TEXTLEN 10000               /* Maximum length of text */
#define BUFFERSIZE 100            /*    Input buffer size */
#define MAXWORDS 500
#define WORDLEN 15            

int main(void)
{
    char text[TEXTLEN + 1];
    char buffer[BUFFERSIZE];
    char endstr[] = "*\n";            /* Signals end of input */
    
    const char space = ' ';
    const char quote = '\'';
    
    char words[MAXWORDS][WORDLEN + 1];
    int     nword[MAXWORDS];
    char word[WORDLEN + 1];
    int wordlen = 0;
    int wordcount = 0;
    int i = 0;
    
    printf("Enter text on an arbitrary number of lines.");
    printf("\nEnter a line containing just an asterisk to end input:\n\n");
    
    /* Read an arbitrary number of lines of text */
    while(true)
    {
        /* A string containing an asterisk followed by newline */
        /* signals end of input */
        if(!strcmp(fgets(buffer,BUFFERSIZE,stdin),endstr))
            break;
        
        /* Check if we have space for latest input */
        if(strlen(text) + strlen(buffer) + 1 > TEXTLEN)
        {
            printf("Maximun capacity for text exceeded. Terminating program.");
            return 1;
        }
        strcat(text,buffer);
    }
    for(i = 0 ; i < strlen(text) ; i++ )
    {
        if(text[i] == quote || isalnum(text[i]))
            continue;
        text[i] = space;
    }
    int index = 0;
    while(true)
    {
        while(text[index] == space)
        ++index;
        if(text[index] == '\0')
        break;
        wordlen = 0;
        while(text[index] == quote || isalpha(text[index]))
        {
            if(wordlen == WORDLEN)
            {
                printf("Maximum word lengthe exceeded.Terminating program");
                return 1;
            }
            word[wordlen++] = tolower(text[index++]);
        }
        word[wordlen] = '\0';
        bool isnew = true;
        for(i = 0 ; i < wordcount ; i++)
            if(strcmp(word,words[i]) == 0)
            {
                ++nword[i];
                isnew = false;
                break;
            }
            if(isnew)
            {
                if(wordcount >= MAXWORDS)
                {
                    printf("\n Maximum word count exceeded. Terminating program");
                    return 1;
                }
                strcpy(words[wordcount],word);
                nword[wordcount++] = 1;
            }
    }
   
    for(i = 0 ; i < wordcount ; i++)
    {
        if( !(i%3))
            printf("\n");
        printf(" %-15s%5d",words[i], nword[i]);
    }
    system("pause");
    return 0;
}

 

#include<stdio.h>
#include<string.h>
#include<ctype.h>
#define Maxw 100
#define Maxi 10000 
int main(void)
{
    char word[Maxw];
    char input[Maxi];
    char newinput[100][15];
    const char space=' ';
    int count=0;
    int i=0;
    int d=0;
    printf("This programe will extract words except ','and other signs.");
    printf("\nNow enter the words in array input:\n");
    gets(input);
    printf("%d ",strlen(input));
    for(i=0;i<strlen(input);i++)
    {
        if(input[i]==space  || isalpha(input[i]))
            continue;
        input[i]=space;
        
    }
    printf("%s\n",input);
    input[strlen(input)]='\0';

    while(1)
    {
        /*if(i==Maxw || count==Maxi)
        { 
        printf("Terminate.");
        return 1;
        }*/

        i=0;
        while(input[count]==space)
            ++count;
        if(input[count]=='\0')
            break;
        while(isalpha(input[count]))
            word[i++]=input[count++];
        word[i]='\0';
        if(d==100)
        {
            printf("Terminate!");
            return 1;
        }
        strcpy(newinput[d],word);
        d++;
    }
    for(i=0;i<d;i++)
        printf("%-15s\n",newinput[i]);
        system("pause");

    return 0;
}