实验4

#include<math.h>
#include<stdio.h>
void solve(double a,double b,double c);

int main(){
    double a,b,c;
    printf("Enter a,b,c:");
    
    while(scanf("%lf%lf%lf",&a,&b,&c)!=EOF){
        solve(a,b,c);
        printf("Enter a,b,c");
    }
    return 0;
}

void solve(double a,double b,double c){
    double x1,x2;
    double delta,real,imag;
    
    if(a==0)
       printf("not quadrativ equation.\n");
    else{
        delta=b*b-4*a*c;5
        
        if(delta>=0){
            
            x1=(-b+sqrt(delta)/(2*a));
            x2=(-b-sqrt(delta)/(2*a));
            printf("x1=%f,x2=%f\n,x1,x2");
            
        } 
        else{
            
            real=-b/(2*a);
            imag=sqrt(-delta)/(2*a);
            printf("x1=%f+%fi,x2=%f-%fi\n",real,imag,real,imag);
            
            
           
    } 
}
    
    

能

#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!=%11d\n",i,fac(i));
    
    return 0;
    
}
long long fac(int n){
    static long long p=1;
    
    p=p*n;
    printf("p=%11d\n",p);
    
    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>
# 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-1];
    
    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>
long long fun(int n);

int main(){
    int n;
    long long f;
    while(scanf("%d",&n)!=EOF){
        f=fun(n);
        printf("n=%d,f=%11d\n",n,f);
        
    }
     return 0;
}


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

#include <stdio.h>
void draw(int n, char symbol);
#include <stdio.h>
int main() 
{
    int n, symbol;
    while(scanf("%d %c", &n, &symbol) != EOF) 
    {
        draw(n, symbol); 
        printf("\n");
    }
    return 0;
}

void draw(int n,char symbol)
{
    int i,k,j;
    for(i=1;i<=n;i++)
    {
        for(k=1;k<=n-i;k++)
        printf(" ");
        for(j=1;j<=(2*i-1);j++)
        {
            printf("%c",symbol);
        }
        printf("\n");
    }
}

实验总结：通过这次实验，我对自己新定义函数与数组有了更深的认识与理解。更加熟练的掌握了使用EOF，和打印字符，通过for循环语句的使用。自己一开始不太容易相出来该如何设计函数。后来询问一下同学或老师才做出来。就是觉得更应该勤加练习。