c简单代码

//---------------------1
#include<stdio.h>
void main()
{
    int a,b,c;
    printf("输入三个正整数,a,b,c");
    scanf("%d%d%d",&a,&b,&c);
    if(a>b&&a>c)//很好的算法，求出三个数的最大值
        if(b>c)
            printf("%d%d%d\n",a,b,c);
        else
            printf("%d%d%d",a,c,b);
    else if(b>a&&b>c)
            if(a>c)
                printf("%d%d%d\n",b,a,c);
            else
                printf("%d%d%d\n",b,c,a);
    else
            if(a>b)
                printf("%d%d%d\n",c,a,b);
            else
                printf("%d%d%d\n",c,b,a);
}
//---------------2
#include<stdio.h>
void main()
{
    int a,b,c,t;
    printf("输入三个正整数a,b,c");
    scanf("%d%d%d",&a,&b,&c);
    if(a<b)
    {t=a;a=b;b=t;}
    if(a<c)
    {t=b;a=c;c=t;}
    if(b<c)
    {t=b;b=c;c=t;}
    printf("%d%d%d\n",a,b,c);
}
//----------------------------3
#include<stdio.h>
void main()
{
    int g;
    printf("输入成绩:g");
    scanf("%d",&g);
    if(g>=85&&g<=100)
        printf("优秀");
    else
        if(g>=75&&g<=84)
            printf("良好");
        else
            if(g>=64&&g<=74)
                printf("及格");
            else
                printf("不及格");
}
//----------------------4
#include<stdio.h>
void main()
{
    int d;
    printf("输入一个正整数:\n");
    scanf("%d",&d);
    switch (d)
    {
    case 1:printf("monday\n");break;
    case 2:printf("tuesday\n");break;
    case 3:printf("wednesday\n");break;
    case 4:printf("thursday\n");break;
    case 5:printf("friday\n");break;
    case 6:printf("saturday\n");break;
    case 7:printf("sunday\n");break;
    default:printf("you input error?\n");break;
    }
}
//---------------------------------5
#include<stdio.h>
void main()
{
    int year,month;
    printf("输入年和月:");
    scanf("%d%d",&year,&month);
    switch (month)
    {
    case 1:
    case 3:
    case 5:
    case 7:
    case 8:
    case 10:
    case 12:
        printf("%d%d has 31 days\n.",year,month);break;
    case 4:
    case 6:
    case 9:
    case 11:
        printf("%d%d has 30 days\n",year,month);break;
    case 2:
        if(year%4==0&&year%100!=0||year%400==0)
        {printf("%d%d has 29 days\n.",year,month);break;}
        else
        {

            printf("%d%d has 28 days\n.",year,month);break;
        }
    default:
        printf("you input error!\n");
    }
}
//-----------------------------6
#include<stdio.h>
void main()
{
    int c;
    printf("Enter 1 or 0");
    scanf("%d",&c);
    while(c==1)
    {
        printf("*******\n");
        printf("Enter 1 or 0");
        scanf("%d",&c);//突然想起和那个递归的形式差不多
    }
}
//-----------------------------7
#include<stdio.h>
void main()
{
    int c;
    do
    {
        printf("*******\n");
        printf("Enter 1 or 0");
        scanf("%d",&c);
    }while (c==1);
}
//-----------------------------8
#include<stdio.h>
void main()
{
    int i,n;
    printf("Enter role n:");
    scanf("%d",&n);
    for(i=0;i<=n;i++)//n+1行
    {
        printf("*******");
        printf("\n");
    }
}
//-----------------------------9
#include<stdio.h>
void main()
{
    int i,s=0;
    for(i=1;i<=10;i++)
    {
        s=s+i;
    }
    printf("s=%d\n",s);
}
//---------------------------------10
#include<stdio.h>
void main()
{
    int i,n,t=1;
    printf("Enter n:");
    scanf("%d",&n);
    for(i=1;i<=n;i++)
    {
        t=t*i;
    }
    printf("t=%d\n",t);
}
//------------------------------------11
#include<stdio.h>
void main()
{
    int i,k,n;
    printf("Enter n?");
    scanf("%d",&n);
    k=n-1;
    for(i=2;i<=k;i++)//判断能否被2到n-1之中的任何一个数整除
    {
        if(n%i==0)
            break;//n不是素数就跳出循环体,跳出的是for循环，接着还要执行下一个语句
    }
    if(i>k)//执行到最后，如果是素数的话，i=n>k;否则不是素数
        printf("%d is 素数\n",n);
    else
    {
        printf("%d not is 素数\n",n);
    }
}
//-------------------12
#include<stdio.h>
void main()
{
    int i,s=0,n;
    printf("Enter n?");
    for(i=1;i<=10;i++)
    {
        scanf("%d",&n);
        if(n%2!=0)
            continue;//n不是偶数跳出本次循环，continue是跳出本次的一次for循环，而break则是整个for循环，然后执行下一个语句
        s=s+n;//2 4 6 8 10之和
    }
    printf("%d\n",s);
}
//------------------------------13
#include<stdio.h>
void main()
{
    char ch;
    printf("input char:");
    while ((ch=getchar())!='*')//不等于'*'才进行循环,=的优先级低于！=
    {
        if(ch>='0'&&ch<='9')
            continue;
        putchar(ch);
    }
    printf("\n");
}
//----------------------------14
#include<stdio.h>
void main()
{
    int i,t,n,s=0;
    for(n=1;n<=10;n++)
    {
        t=1;
        for(i=1;i<=n;i++)
        {
            t=t*i;
        }
        printf("%d!=%d\n",i-1,t);
        s=s+t;
    }
    printf("s=%d",s);
}
//----------------------------------15
#include<stdio.h>
void main()
{
    int i,k,n;
    printf("2;");//首先输出素数2
    for(n=3;n<=100;n++)//从三循环到100
    {
        k=n-1;
        for(i=2;i<=k;i++)//最先执行i=2,由于2小于3，故2+1=3;然后进行下面的运算
        {
            if(n%i==0)
                break;
        }
        if(i>k)
            printf("%d;",n);
    }
}
//-----------------------------16
#include<stdio.h>
void main()
{
    int i,k,n,j=1;
    printf("2; ");
    for(n=3;n<100;n++)
    {
        k=n-1;
        for(i=2;i<=k;i++)
        {
            if(n%i==0)
                break;
        }
        if(i>k)
        {
            printf("%d;",n);
            j++;
            if(j==8)
            {
                printf("\n");
                j=0;
            }
        }
    }
}
//---------------------------------17
#include<stdio.h>
void main()
{
    int i,j;
    printf("1 2 3 4 5 6 7 8 9\n");//输出列号
    for(i=1;i<=9;i++)
    {
        printf("%d",i);//输出行号
        for(j=1;j<=i;j++)
        {
            printf("%d ",i*j);
        }
        printf("\n");
    }
}
//-----------------------------18
#include<stdio.h>
void main()
{
    int i,j;
    for(i=1;i<=5;i++)//输出的行数
    {
        for(j=1;j<=5-i;j++)//输出每行左边的空格
            printf(" ");
        for(j=1;j<=i;j++)
            printf(" %d ",i);//输出每行的数字
        putchar('\n');//输出换行符
    }
}
//-------------------------------------19
#include<stdio.h>
void main()
{
    int g,i,sum,max;
    printf("Please input student's grade:\n");
    scanf("%d",&g);
    max=g;
    sum=g;
    for(i=1;i<=9;i++)
    {
        printf("Please input student's grade:\n");
        scanf("%d",&g);
        sum=sum+g;
        if(max<g)
            max=g;
    }
    printf("highest score=%d\n",max);
    printf("total score=%d\n",sum);
}
//------------------------------20
#include<stdio.h>
void main()
{
    int score[10],i,sum,max;
    printf("Please input student's grade:\n");
    for(i=0;i<10;i++)
        scanf("%d",&score[i]);
    sum=0;
    max=score[0];
    for(i=0;i<10;i++)
    {
        sum=sum+score[i];
        if(score[i]>max)
            max=score[i];
    }
    printf("highest score=%d\n",max);
    printf("total score=%d\n",sum);
}
//------------------------------21
#include<stdio.h>
void main()//斐波那契数列
{
    int fib[12],k;
    fib[0]=1;
    fib[1]=1;
    for(k=2;k<12;k++)
        fib[k]=fib[k-1]+fib[k-2];
    for(k=0;k<12;k++)
        printf("%d",fib[k]);
    printf("\n");
}