实验3

#include<stdio.h>

#include<stdlib.h>

#include<time.h>
#include<windows.h>
#define N 80

void print_text(int line, int col, char text[]);
void print_spaces(int n);
void print_blank_lines(int n);

int main()
{
    int line, col, i;
    char text[N] = "hi,November~";

    srand(time(0));
    for (i = 1; i <= 10; ++i)
    {
        line = rand() % 25;
        col = rand() % 80;
        print_text(line, col, text);
        Sleep(1000);
    }
    return 0;
}

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

void print_text(int line, int col, char text[])
{
    print_blank_lines(line - 1);
    print_spaces(col - 1);
    printf("%s", text);
}

 该程序实现的功能是：实现hi，november的动画效果

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

int main()
{
    int i, n;

    printf("Enter n:");
    scanf_s("%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;

    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;
}

static变量的特性：静态局部变量，只赋值一次，每次调用函数时保留上次函数调用的值

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

int main()
{
    int n;
    long long f;

    while (scanf_s("%d", &n) != EOF)
    {
        f = func(n);
        printf("n=%d,f=%lld\n", n, f);
    }
    return 0;
}

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

}

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

int main()
{
    int n, m;

    while (scanf_s("%d%d", &n, &m) != EOF)
        printf("n=%d,m=%d,ans=%d\n", n, m, func(n, m));

    return 0;
}

int func(int n, int m)
{
    if (n==m||m==0)
    {
        return 1;
    }
    else if(n<m)
    {
        return 0;
    }
    else
    {
        return func(n - 1, m) + func(n - 1, m - 1);
    }
}

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

int main()
{
    
    unsigned int n,a;
    while (scanf_s("%u", &n) != EOF)
    {
        hanoi(n, 'A', 'B', 'C');
        a= pow(2, n) - 1;
        printf("一共移动了%d次", a);
        system("pause");
        
    }
    return 0;
    
}
void hanoi(unsigned int n, char from, char temp, char to)
{
    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("%u:%c-->%c\n", n, from, to);

}

#include <stdio.h>
int mul(int n, int m);
int main() {
    int n, m;
    
    while (scanf_s("%d%d", &n, &m) != EOF)
        printf("%d * %d = %d\n", n, m, mul(n, m));
    return 0;
}

int mul(int n, int m)
{
    if (n == 1)
        return m;
    else if (m == 1)
        return n;
    else if (m == 0 || n == 0)
        return 0;
    else if (m > 0)
        return mul(n, m - 1) + n;
    
}

#include<stdio.h>
int is_prime(unsigned int n);
int main()
{
    int i,a;
    for(i=4;i<=20;i+=2)
    {
        for(a=2;a<i;a++)
        {
            if(2*a<=i&&is_prime(a)&&is_prime(i-a))
            {
                printf("%d=%d+%d\n", i, a,i-a );
                break;
            }
        }
    }
    return 0;
}

int is_prime(unsigned int n)
{
    int j, s=1;
    for (j = 2; j < n; j++)
    {
        if (n % j == 0)
        {
            s = 0;
            break;
        }
    
    }
    
    return s;
}

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

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

long fun(long s)
{
    int a,c;
    int b = 0;
    int d = 0;
    while(s>0)
    {
        if ((s % 10) % 2 == 1)
        {
            a = s % 10;
            b = b * 10 + a;
            
        }
        s /= 10;
    }
    
    while (b > 0)
    {
        c = b % 10;
        d = d * 10 + c;
        b /= 10;
    }
    return d;
}