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); 
}

 任务2

#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;
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;
}

 任务3

#include <stdio.h>
long long func(int n);
int main() {
int n;
long long f;
while (scanf("%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;
    return(func(n-1)*2+1);
}

 任务4

#include <stdio.h>
int func(int n, int m);
int main() {
int n, m;
while(scanf("%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;
    if(n<m)
    return 0;
    return func(n-1,m)+func(n-1,m-1);
}

 任务5

#include <stdio.h>
int mul(int n, int m);
int main() {
int n, m;
while(scanf("%d%d", &n, &m) != EOF)
printf("%d * %d = %d\n", n, m, mul(n, m));
return 0;
}
int mul(int n, int m)
{
    if(m==0||n==0)
    m = 0;
    M = m+mul(n-1,m);
return M；
    
}

 任务6

#include<stdio.h>
#include<stdlib.h>
void hanoi(unsigned n,char from,char temp,char to);
void moveplate(unsigned n,char from,char to);
long count=0;
int main()
{
   unsigned n;
  while( scanf_s("%u",&n)!=EOF)
{   hanoi(n,'A','B','C');
  printf("一共移动了%ld次\n",count);}
system ("pause");
return 0; }
void hanoi(unsigned 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 n,char from,char to)
{printf("%u:%c-->%c\n",n,from,to);
  count++;
}

 任务7

#include <stdlib.h>
#include<stdio.h>
int is_prime(int);
int main() 
{
     int sum,a,b;
     for (sum=2;sum<=20;sum=sum+2)
 {
  for(a=1;a<=17;a++)
      {
   if(is_prime(a))
      {
 for(b=1;b<=17;b++)
          {
 if(is_prime(b)&&a<=          

 if(sum==a+b)
       
  printf("%d =%d + %d",sum,a,b);
  printf("\n");
     }
   system("pause");
}
int is_prime(int n)
{
    int i;
   if (n <= 1)
  return 0;
  for (i = 2; i < n; i++)
   if (n % i == 0)
  return 0;
  return 1;
}

任务8

#include<stdio.h>
#include<stdlib.h>
#include<math.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 munber is:%ld\n\n",t);
        printf("Enter a number: ");}
    system("pause");
    return 0;
}
long fun(long s){
    long ans,m=0;
    int h=1;
    while(s>0)
        { ans=s%10;
        if(ans%2!=0)
        {
            m+=ans*h;
            h=h*10;
        }
        s=s/10;
        }
        return m; 
        }