第七、八周作业

作业一

例题5-3

#include<iostream>using namespace std;double circleArea(double);int main(){double area=circleArea(5.0);cout<<"area="<<area<<endl;return 0;}double circleArea(double r){double pi=3.14;double area=pi*r*r;return area;}

例题5-10

#include<iostream>using namespace std;void display(int x,float y){cout<<x<<" "<<y;return;}int main(){float a;int b;cin>>b>>a;display(b,a);return 0;}

例题5-15

#include<iostream>using namespace std;float Factorial(int n);int main(){int a;float f;cout<<"input an integer number:";cin>>a;f=Factorial(a);cout<<a<<"!="<<f<<endl;return 0;}float Factorial(int n){float fact;if(n==0)fact =1;elsefact =n*Factorial(n-1);return fact;}

作业二

第二题

#include<iostream>  using namespace std;    long intPower(int base,int exponent);    int main()  {      int a,b;      long int c;      cout<<"请输入一个整数以及所要求的整数次幂的次数"<<endl;      cin>>a>>b;      c= intPower(a,b);      cout<<"所求的结果为:"<<endl;      cout<<a<<"的"<<b<<"次幂为:"<<c<<endl;        return 0;  }    long intPower(int base,int exponent)  {      long int d=base;      for(int i=1;i<exponent;i++)          d *= base;            return d;  } 

第三题

#include<iostream>  using namespace std;    int a;  void number(int n)  {      int i;      for(i =2;i<=n;i++)          if(n%i==0)              break;      if(i ==n)          cout<<a<<"是素数"<<endl;      else          cout<<a<<"不是素数"<<endl;  }    int main()  {      char b;      while(1)      {          cout<<"请输入一个正整数"<<endl;          cin>>a;          number(a);          cout<<"若继续请输入Y:"<<endl;          cin>>b;          if(b=='y'||b=='Y')          {              continue;              cout<<endl;         }          else              break;      }        return 0;  } 

第四题

#include<iostream>  #include<math.h>  using namespace std;      long power(int x)  {      int i, t, n, k;        i = 0, t = x, n = 0;        while(t>0)        {            t = t/10;            n++;        }        k = pow(10,n-1);                   while(x>0)        {            t = x%10;            x = x/10;            i += t*k;            k = k/10;        }      return i;  }    int main()  {      int a;long i;    char b;      while(1)      {          cout<<"请输入一个正整数"<<endl;          cin>>a;          i=power(a);          cout<<a<<"的逆转数为:"<<i<<endl;          cout<<"若继续请输入Y:"<<endl;          cin>>b;          if(b=='y'||b=='Y')          {              continue;              cout<<endl;         }          else              break;      }        return 0;  } 

第五题

#include <iostream>  using namespace std;    void degree(int x);    int main()  {      int a;      char b;      while(1)      {          cout<<"请输入分数：";          cin>>a;          degree(a);          cout<<"若继续输入请按Y;";          cin>>b;          if(b == 'Y'||b == 'y')          {              cout<<endl;              continue;          }          else             break;      }          return 0;  }      void degree(int x)  {      switch(x/10)      {          case 6:              {                  cout<<"该学生成绩为D"<<endl<<endl;                  break;              }          case 7:              {                  cout<<"该学生成绩为C"<<endl<<endl;                  break;              }          case 8:              {                  cout<<"该学生成绩为B"<<endl<<endl;                  break;              }          case 9:              {                  cout<<"该学生成绩为A"<<endl<<endl;                  break;              }          default:              cout<<"该学生成绩为不及格"<<endl<<endl;      }  } 

第六题

#include<iostream>  using namespace std;    float power(int n[10]);int main(){      int a[10],k,aver;      char b;      while(1)      {          cout<<"请分别输入10个学生的分数:"<<endl;          for(k=0;k<10;k++)          {              cout<<"a["<<k<<"]="<<endl;              cin>>a[k];          }                 aver=power(a);          cout<<"平均成绩为:"<<aver<<endl;          cout<<"若继续请输入Y:"<<endl;          cin>>b;          if(b=='y'||b=='Y')          {              continue;              cout<<endl;        }          else              break;      }        return 0;  }float power(int n[10])  {      int d=0,e;      for(int i=0;i<10;i++)      {          d+=n[i];      }      e=d/10;        return e;  }  

余下的有难度，暂时不会。。。

作业三

#include<iostream>  #include<iomanip>  using namespace std;    int ji(int a[4][5], int b[5][3]);    int main()  {      int a[4][5],b[5][3],c[4][3]={0},d,e;      cout<<"请输入一个4行5列数组"<<endl;      for(d=0;d<4;d++)      {          for(e=0;e<5;e++)          {              cin>>a[d][e];          }      }      cout<<"请输入一个5行3列数组"<<endl;      for(d=0;d<5;d++)      {          for(e=0;e<3;e++)          {              cin>>b[d][e];          }      }      for(d = 0;d<4;d++)            for(e = 0;e<3;e++)            {                c[d][e] = ji(a,b);            }        cout<<"A矩阵与B矩阵的积为："<<endl;        for(d = 0;d<4;d++)        {            for(e = 0;e<3;e++)            {                cout<<setw(4)<<c[d][e];            }            cout<<endl;        }                    return 0;    }        ji(int a[4][5], int b[5][3])  {      int d,e,f,g,c[4][3]={0};      for(d=0;d<4;d++)              for(e=0;e<3;e++)              {                  for(f=0;f<5;f++)                  {                      g=a[d][e]*b[d][e];                      c[d][e]=c[d][e]+g;                  }                                }            return c[d][e];  }

作业四

#include <iostream>  using namespace std;    float factorial(int n);    int main()  {      int n, i;      char b;      while(1)      {          float s = 0;          cout<<"Please input an integer number: ";          cin>>n;          for(i = 1;i<=n;i++)              s += factorial(i);          cout<<"s"<<"["<<n<<"] = "<<s<<endl<<endl;          cout<<"若继续输入请按Y:";          cin>>b;          if(b == 'Y'||b == 'y')          {              cout<<endl;              continue;          }          else            break;        }        return 0;  }    float factorial(int n)  {      float fact;      if(n == 0)      {          fact = 1;      }      else          fact = n*factorial(n-1);        return fact;  }

这题不就是例题嘛。。。。