作业 1 熟悉C语言编程环境第五章

#include<stdio.h>
int main(void)
{
double height,radius,volume;
double cylinder(double r,double h);

printf("Enter radius and height:");
scanf("%lf%lf",&radius,&height);
volume=cylinder(radius,height);
printf("Volume=%.3f\n",volume);
return 0;
}
double cylinder(double r, double h)
{
double result;

result=3.1415926*r*r*h;

return result;
}

int event(int n)
{
if(n%2==0)
return 1;
else
return 0;
}

#include<stdio.h>
#include<math.h>
int main(void)
{
double e,pi;
double funpi(double e);

printf("Enter e:");
scanf("%lf",&e);
pi=funpi(e);
printf("pi=%f\n",pi);
return 0;
}
double funpi(double e)
{
int denominator,flag;
double item,sum;

flag=1;
denominator=1;
item=1.0;
sum=0;
while(fabs(item)>=e){
item=flag*1.0/denominator;
sum=sum+item;
flag=-flag;
denominator=denominator+2;
}
return sum*4;
}

#include<stdio.h>
#include<math.h>
int main(void)
{
int count,m;
int prime(int m);
count=0;
for(m=2;m<=100;m++){
if(prime(m)!=0){
printf("%6d",m);
count++;
if(count%10==0)  printf("\n");
}
}
printf("\n");
}
int prime(int m)
{
int i,n;
if(m==1) return 0;
n=sqrt(m);
for(i=2;i<=n;i++)
if(m%i==0){
return 0;
}
return 1;
}

#include<stdio.h>
int main(void)
{
void pyramid(int n);

pyramid(5);

return 0;
}
void pyramid(int n)
{
int i,j;

for(i=1;i<=n;i++){
for(j=1;j<=n-i;j++)
printf(" ");
for(j=1;j<=i;j++)
printf(" %d",i);
putchar('\n');
}
}

#include<stdio.h>
float result_real,result_imag;
int main(void)
{
float imag1,imag2,real1,real2;
void complex_prod(float real1,float imag1,float real2,float imag2);
void complex_add(float real1,float imag1,float real2,float imag2);
printf("Enter 1st complex number(real and imaginary):");
scanf("%f%f",&real1,&imag1);
printf("Enter 2nd complex number(real and imaginary):");
scanf("%f%f",&real2,&imag2);
complex_add(real1,imag1,real2,imag2);
printf("addition of complex is %f+%fi\n",result_real,result_imag);
complex_prod(real1,imag1,real2,imag2);
printf("product of complex is %f+%fi\n",result_real,result_imag);
return 0;
}
void complex_add(float real1,float imag1,float real2,float imag2)
{
result_real=real1+real2;
result_imag=imag1+imag2;
}
void complex_prod(float real1,float imag1,float real2,float imag2)
{
result_real=real1*real2-imag1*imag2;
result_imag=real1*imag2+real2*imag1;
}

#include<stdio.h>
int x;
int f();
int main(void)
{
int a=1;
x=a;
a=f();
{
int b=2;
b=a+b;
x=x+b;
}
printf("%d%d",a,x);
return 0;
}
int f()
{
int x=4;
return x;
}

#include<stdio.h>
float cash;
int main(void)
{
int choice;
float value;
void income(float number),expend(float number);
cash=0;
printf("Enter operate choice(0--end,1--income,2--expend):");
scanf("%d",&choice);
while(choice!=0){
if(choice==1||choice==2){
printf("Enter cash value:");
scanf("%f",&value);
if(choice==1)
income(value);
else
expend(value);
printf("current cash:%.2f\n",cash);
}
printf("Enter operate choice(0--end,1--income,2--expend):");
scanf("%d",&choice);
}
return 0;
}
void income(float number)
{
cash=cash+number;
}
void expend(float number)
{
cash=cash-number;
}

#include<stdio.h>
double fact_s(int n);
int main(void)
{
int i,n;
printf("Input n:");
scanf("%d",&n);
for(i=1;i<=n;i++)
printf("%3d!=%.0f\n",i,fact_s(i));
return 0;
}
double fact_s(int n)
{
static double f=1;
f=f*n;
return(f);
}