实验4

#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)
{
    if(n == 1)
        return 1;
    else
        return 2*(fun(n-1)+1)-1;   
}

#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>
long long fac(int n); // 函数声明
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;
}
// 函数定义
long long fac(int n) {
static long long p = 1;
printf("p = %lld\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);
}

#include <stdio.h>
#include <stdlib.h> 
#define N 1000
int fun(int n,int m,int bb[N]) {
    int i,j,k=0,flag;
    
    for(j=n;j<=m;j++) {
         flag=1 ;   
        for(i=2;i<j;i++)
            if(j%i==0) {  
                   flag=0;
                   break;
        }
        if(flag==1) 
           bb[k++]=j;
    }
    return k;
}

int main(){
    int n=0,m=0,i,k,bb[N];
    
    scanf("%d",&n);
    scanf("%d",&m);
    
    for(i=0;i<m-n;i++)
        bb[i]=0;
        
    k=fun(n,m,bb); 
    
    for(i=0;i<k;i++)
        printf("%4d",bb[i]);
        
    return 0;
}

#include <stdio.h>
void dec2n(int x, int n);  // 函数声明 

int main() {
    int x;
    
    printf("输入一个十进制整数: ");
    scanf("%d", &x);
    
    dec2n(x, 2);    
    dec2n(x, 8);     
    dec2n(x, 16);    
    
    return 0;
}
 
void dec2n(int x, int n) {
    int i,b,a[100];
    for(i=0;x!=0;i++){
        a[i]=x%n;
        x=x/n;
    }
    if(a[i]>9)
    switch(a[i]){
        case 10:a[i]=‘A‘;break;
        case 11:a[i]=‘B‘;break;
        case 12:a[i]=‘C‘;break;
        case 13:a[i]=‘D‘;break;
        case 14:a[i]=‘E‘;break;
        case 15:a[i]=‘F‘;break;
    }
    printf("\n");
    for(b=i-1;b>=0;b--){
        printf("%d",a[b]);
    }
    
}