实验三

tesk1

#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);
}

task2.1

#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 = p * n;
    return p;
}

task2.2

#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;
}

task3

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

long long fun(int n)
{
    static int s = 1;
    int k;
    if (n > 1)
    {
        s = s * 2;
        fun(n - 1);
    }
    if (n == 1)
    {
        k = s;
        s = 1;
        return 2*k-1;

    }

}

task4

#include <stdio.h>

int m = 0;

void move(char a, int n, char c)
{
    m++;
    printf("第%d个盘：%c-->%c.\n", n, a, c);
}

void hanoi(int n, char a, char b, char c)
{
    if (n == 1)
        move(a, 1, c);
    else
    {
        hanoi(n - 1, a, c, b);
        move(a, n, c);
        hanoi(n - 1, b, a, c);
    }
}

int main()
{
    int n;

    while (scanf_s("%d", &n) != EOF)
    {
        hanoi(n, 'A', 'B', 'C');
        printf("一共移动了%d次\n", m);
    }
    return 0;
}

task5

#include<stdio.h>
#include<math.h>
int is_prime(int n);
int main()
{
    int n, s1, s2, f1, f2;
    while (scanf_s("%d", &n) != EOF)
    {
        for (s1 = 2; s1 <= (n / 2); s1++)
        {
            f1 = is_prime(s1);
            if (f1 == 1)
            {
                s2 = n - s1;
                f2 = is_prime(s2);
                if (f2 == 1)
                {
                    printf("%d = %d + %d\n", n, s1, s2);
                }
            }
        }
    }
    return 0;
}

int is_prime(int s)
{
    int i, t;
    for (i = 2; i < s; ++i)
    {
        if (s % i == 0)
        {
            break;
        }
    }
    if (i == s) return 1;
    else return 0;
}

task6

#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 i, m = 0, k = 0;
    while (s != 0)
    {
        i = s % 10;
        s /= 10;
        m = m * 10 + i;
    }
    while (m != 0)
    {
        i = m % 10;
        m /= 10;
        if (i % 2 == 1)
        {
            k = k * 10 + i;
        }
    }
    return k;
}