实验3 函数

TASK 1

在80个输出0~25以内的行数和0~80以内的空格，再在随机输出的行数与空格后面输出“hi, MAY”

#include<stdio.h>
#include<stdlib.h>
#include<time.h>
#include<windows.h>
#define N 80
void printText(int line,int col,char text[]);
void printSpaces(int n);
void printBlankLines(int n);

int main()
{
    int line,col,i;
    char text[N]="hi,May~";
    
    srand(time(0));
    for(i=1;i<=10;++i)
    {
        line=rand()%25;
        col=rand()%80;
        printText(line,col,text);
        Sleep(1000);
    }
    return 0;
}

void printSpaces(int n)
{
    int i;
    
    for(i=1;i<=n;++i)
        printf("");
}

void printBlankLines(int n)
{
    int i;
    for(i=1;i<=n;++i)
        printf("\n");
}

void printText(int line,int col,char text[])
{
    printBlankLines(line-1);
    printSpaces(col-1);
    printf("%s",text);
}

 

 

TASK 2

局部 static 变量 ：除非下一次赋值，那么static定义的变量不变

#include<stdio.h> 
long long fac(int n);

int main()
{
    int i,n;
    
    printf("Enter n:");
    scanf("%d",&n);
    
    for(i=1;i<=n;++i)
        printf("%d!=%lld\n",i,fac(i));
    
    return 0;
}

long long fac(int n)
{
    static long long p=1;
    printf("p=%11d\n",p);
    p=p*n;
    
    return p;
}

 

#include<stdio.h>
int func(int,int);

int main()
{
    int k=4,m=1,p1,p2;
    
    p1=func(k,m);
    p2=func(k,m);
    
    printf("%d,%d\n",p1,p2);
    
    return 0;
}

int func(int a,int b)
{
    static int m=0,i=2;
    
    i+=m+1;
    m=i+a+b;
    
    return m;
}

 

task 3

#include<stdio.h>
long long fun(int n);

int main()
{
    int n;
    long long f;
    
    while(scanf("%d",&n)!=EOF)
    {
        f=fun(n);
        printf("n = %d,f = %lld\n",n,f);
    }
    
    return 0;
} 

long long fun(int n)
{
    
    long long f;
    
    if(n==0)
        f=1;
    else if(n==1)    
        f=1;
    else
        f=2*fun(n-1)+1;
    
    return f;
}

 

 

TASK 4

//task 4//
#include<stdio.h>
#include<math.h>
void hanoi(unsigned int n,char from,char temp,char to);
void moveplate(unsigned int n,char from,char to);
unsigned int count(unsigned int n);


int main()
{
    unsigned int m;
    
    while(scanf("%u",&m)!=EOF)
    {
        
        hanoi(m,'A','B','C');
        
        
        printf("\n一共移动了%u次.\n",count(m));
    }
    
    return 0;
}

void hanoi(unsigned int n,char from,char temp,char to)
{
    int i;
    
    if(n==1)
        moveplate(n,from,to);
    else
    {
        hanoi(n-1,from,to,temp);
        moveplate(n,from,to);
        hanoi(n-1,temp,from,to);
    }
}

void moveplate(unsigned int n,char from,char to)
{
    printf("第%u个盘子: %c-->%c\n",n,from,to);
}

unsigned int count(unsigned int n)
{
    if(n>=2)
    return 2*count(n-1)+1;
    else
    return 1;
}

 

 

 

TASK 5

//task 5//
#include<stdio.h>
#include<math.h> 
#define N 20
int is_prime(int n);

int main()
{
    int i;
    int num;
    
    for(num=4;num<=N;num+=2)
    {
        for(i=2;i<=num/2;i++)
        {
            if(is_prime(i)&&is_prime(num-i))
                printf("%d = %d + %d\n",num,i,num-i);
                
                
        }
    }
    
    return 0;
} 

int is_prime(int n)
{
    int i;
    
    if(n==1)return 1;
    for(i=2;i<=sqrt(n);i++)
    {
        if(n%i==0)return 0;
    }
    
    return 1;
}

 

 

 TASK 6

#include<stdio.h>
#include<math.h>
long fun(long s);

int main()
{
    long s,t;
    
    printf("Enter a number:");
    
    while(scanf("%ld",&s)!=EOF)
    {
        t=fun(s);
        printf("new number is:%ld\n\n",t);
        printf("Enter a number:");
    }
    
    return 0;

} 
long fun(long s)
{
    long n= 1;
    int t=0, d;

    while (s > 0)
    {
        d = s % 10;

        if (d % 2 != 0)
        {
            t = d * n + t;
            n*= 10;
        }
        s /= 10;
    }

    return t;
}