C++语言程序设计(8)

C++语言程序设计

int i,c1=0,c2=0;

for (i=0; i<10; i++)

if (a[i]>0)

c1++;

else

c2++;

cout <<"正数："<<c1<<endl;

cout <<"负数："<<c2<<endl;

}

11．求1至N之间的所有质数。(设N的值由键盘输入)

# include <iostream.h>

# include <math.h>

void main()

{

int N;

cout <<"输入一个正整数：";

do {

cin >>N;

}while (N<=0);

cout <<"1至"<<N<<"之间的所有质数是：2";

for (int m=3; m<=N; m++)

{

int i,tmp=(int)sqrt(m);

for (i=2; i<=tmp; i++)

if (m%i==0) break;

if (i>tmp)