第六周作业

1

例4.1

#include<iostream>using namespace std;int main(){int a[10];int i;for(i=0;i<10;i++)a[i]=i*2+2;for(i=0;i<10;i++){cout<<a[i]<<'\t';if((i+1)%5==0)cout<<endl;}return 0;}

 

例4.2

#include<iostream>using namespace std;int main(){int i,math[40],n;float aver=0.0;int unpassedcount=0;int highscorecount=0;cout<<"请输入学生人数:";cin>>n;cout<<"请输入成绩:";for(i=0;i<n;i++){cin>>math[i];aver+=math[i];}aver/=n;for(i=0;i<n;i++){if(math[i]<60)unpassedcount++;if(math[i]>=90)highscorecount++;}cout<<"平均分为:"<<aver<<endl;    cout<<"90分以上的人数为:"<<highscorecount<<endl;cout<<"不及格的人数为:"<<unpassedcount<<endl;return 0;}

 

4.3

#include<iostream>#include<iomanip>using namespace std;int main(){int a[10],i,big;cout<<"please input 10numbers:\n";for(i=0;i<10;i++)cin>>a[i];cout<<"the numbers are:";for(i=0;i<10;i++)cout<<setw(4)<<a[i];cout<<endl;big=a[0];for(i=1;i<10;i++)if(a[i]>big)big=a[i];cout<<"the bigmumber is :"<<big<<endl;return 0;}

 

4.4

#include<iostream>#include<iomanip>using namespace std;int main(){int a[10];int i,j,t;cout<<"please input 10numbers:\n";for(i=0;i<10;i++)cin>>a[i];cout<<"the numbers are:";for(i=0;i<10;i++)cout<<setw(4)<<a[i];cout<<endl;for(i=1;i<9;i++)for(i=1;j<9-i;j++)if(a[i]>a[j+1]){t=a[j];a[j]=a[+1];a[j+1]=t;}cout<<"the sorted numbers are:"; cout<<endl;return 0;}

 4.5

#include "stdafx.h"#include<iostream>  #include<iomanip>  using namespace std;  int main()  {      int i;      int f[40]={1,1};      for(i=2;i<40;i++)          f[i]=f[i-2]+f[i-1];      for(i=0;i<40;i++)      {          if(i%4==0)              cout<<endl;          cout<<setw(12)<<f[i];      }cout<<endl;    return 0;}

4.6

#include "stdafx.h"#include<iostream>  #include<iomanip>  using namespace std;  int main()  {      int i,j,a[5][5];      for(i=0;i<5;i++)      for(j=0;j<5;j++)      if(i%2==0)      a[i][j]=i*5+j+1;     else      a[i][4-j]=i*5+j+1;     for(i=0;i<5;i++)          { for(j=0;j<5;j++)     cout<<setw(4)<<a[i][j];      cout<<endl;          }  return 0;}

4.7

#include "stdafx.h"#include<iostream>  #include<iomanip>  using namespace std;  int main()  {      int i, j, t, n, m;      int a[2][3];      cout<<"请输入二维数组的元素值:"<<endl;      for(i = 0;i<2;i++)      {          for(j = 0;j<3;j++)          {              cout<<"a"<<"["<<i<<"]"<<"["<<j<<"] = ";              cin>>a[i][j];          }      }      cout<<"该二维数组为："<<endl;      t = a[0][0];      for(i = 0;i<2;i++)      {                 for(j = 0;j<3;j++)          {              cout<<setw(4)<<a[i][j];              if(a[i][j]>t)              {                  t = a[i][j];                  n = i, m = j;              }          }          cout<<endl;      }      cout<<"该数组中最大的元素值为："<<"a"<<"["<<n<<"]"<<"["<<m<<"] = "<<t<<endl;    return 0;}

4.8

#include "stdafx.h"#include<iostream>  using namespace std;    int main()  {      char str[50];      cout<<"Please input strings:";      cin.get(str,50);                cout<<"The strings is:";      cout<<str<<endl;      return 0;}

4.9

#include "stdafx.h"#include<iostream>  #include<cstring>  using namespace std;    int main()  {     char str[100];     cout<<"请输入一个字符串:";     cin.get(str,100);     cout<<"字符串"<<str<<"的反向字符串为:";     for(int i=strlen(str)-1;i>=0;i--)                cout<<str[i];     cout<<endl;    return 0;}

4.10

#include "stdafx.h"#include<iostream>  using namespace std;        int main()    {        char s[]="This is C programming test.";        int i=0,pLen=0,maxpLen = 0, pSeat = 0;        while(s[i]!='\0')        {            while(s[i]!=' '&&s[i]!='\0')            {                pLen++;                i++;            }            if(pLen>maxpLen)                 {                pSeat=i-pLen;                maxpLen=pLen;            }            while(s[i]==' ')                i++;            pLen=0;               }        cout <<"最长的单词 :";        for(i=0;i<maxpLen;i++)            cout << s[pSeat+i];        cout <<endl;            return 0;}

4.11

#include "stdafx.h"#include<iostream>  #include<iomanip>  using namespace std;    int main()  {      char str[50];      cout<<"Please input a string:";      cin.get(str,50);      cout<<"The length of string "<<str<<" is "<<strlen(str)<<endl;    return 0;}

4.12

#include "stdafx.h"#include<iostream>  #include<cstring>  using namespace std;    int main()  {      char str[10];      cout<<"请输入字符串，直到输入 hello 后程序结束:"<<endl;      do{          cin>>str;      }while(strcmp(str,"hello")!=0);        return 0;}

4.13

#include "stdafx.h"#include<iostream>  using namespace std;    int main()  {       char str[50];       int len=0;       cout<<"请输入一个字符串:";       cin.get(str,50);       while(str[len] !='\0')           len++;       cout<<"字符串"<<str<<"的长度"<<len<<endl;          return 0;}

2.习题

1.

#include "stdafx.h"#include<iostream>#include<iomanip>  using namespace std;    int main()  {       int n[5],i,j,temp; cout<<"请输入5个数:\n"; for(i=0;i<5;i++) cin>>n[i]; for(i=0;i<4;i++) for(j=0;j<4-1;j++) if(n[j]<n[j+1]) {temp=n[j];n[j]=n[j+1];n[j+1]=temp;} cout<<"从大到小分别为: "; for(i=0;i<5;i++) cout<<setw(4)<<n[i]; cout<<endl;      return 0;}

2.

#include "stdafx.h"#include<iostream>#include<iomanip>  using namespace std;    int main()  {      int n[2][3],j,i;cout<<"请输入6个数组元素:\n";for(i=0;i<2;i++)for(j=0;j<3;j++){cin>>n[i][j];}int row=0,col=0,max=n[0][0];for(i=0;i<2;i++)for(j=0;j<3;j++)if(max<n[i][j]){max=n[i][j];row=i;col=j;}cout<<"最大的数组元素为: "<<n[row][col]<<endl;      return 0;}

3.

#include "stdafx.h"#include<iostream>#include<iomanip>  using namespace std;    int main()  {      int i,sixteenth,count=0,fib[20]={1,1};for(i=2;i<20;i++){fib[i]=fib[i-2]+fib[i-1];if(fib[i]>=100 && fib[i]<=999)count++;}sixteenth=fib[15];for(i=0;i<20;i++){if(i>0 && i % 4==0)cout<<endl;cout<<setw(8)<<fib[i];}cout<<endl<<endl<<"fibonacci数列前20个数中3位数的个数为:"<<count<<endl<<"fibonacci数列中第16项数据为:"<<sixteenth<<endl;      return 0;}

4.

#include "stdafx.h"#include<iostream>#include <iostream>  using namespace std;    int main()  {      int i,j, n, m, k, t;      j = n = m = k = t = 0;      char str[100];      cout<<"请输入一行文字：";      cin.get(str,100);      for(i = 0;i<100&&str[i]!='\0';i++)      {          if(str[i] >= 'A'&&str[i] <= 'Z')              j++;          else if(str[i] >= 'a'&&str[i] <='z')              n++;          else if(str[i] >='0'&&str[i] <= '9')              m++;          else if(str[i] == ' ')              k++;          else               t++; }      cout<<"大写字母有 "<<j<<" 个。"<<endl;      cout<<"小写字母有 "<<n<<" 个。"<<endl;      cout<<"空格有 "<<k<<" 个。"<<endl;      cout<<"数字有 "<<m<<" 个。"<<endl;      cout<<"其他字符有 "<<t<<" 个。"<<endl;    return 0;}

5.

#include "stdafx.h"#include <iostream>  using namespace std;    int main()  {      int i;      char str[100];      cout<<"请输入一个字符串：";      cin.get(str,100);      cout<<"这个字符串"<<str<<"的反向字符串为：";      for(i = strlen(str)-1;i>=0;i--)      {          cout<<str[i];      }      cout<<endl;      cout<<"这个字符串的长度为："<<strlen(str)<<endl;    return 0;}

6.

#include "stdafx.h"#include <iostream>  using namespace std;    int main()  {      int i, j =0;      char str1[100], str2[100];      cout<<"请输入字符串：";      cin.get(str1,100);      for(i = 0;i<100&&str1[i]!='\0';i++)      {          if(!(str1[i]>='0'&&str1[i]<='9'))          {              str2[j] = str1[i];              j++;          }      }      str2[j+1] = '\0';      cout<<"原字符串："<<str1<<endl;      cout<<"改动后的字符串："<<str2<<endl;      cout<<"改动后字符串的长度："<<j<<endl;        return 0; }

作业3.

#include "stdafx.h"#include <iostream>   #include <iomanip>  using namespace std;   int main()   {       int a[4][5], b[5][3], c[4][3];      int i, j, k, t = 0;      cout<<"请输入A矩阵[4][5]："<<endl;      for(i = 0;i<4;i++)      {          for(j = 0;j<5;j++)          {              cout<<"a["<<i<<"]"<<"["<<j<<"] = ";              cin>>a[i][j];          }      }            cout<<"请输入B矩阵[5][3]："<<endl;      for(i = 0;i<5;i++)      {          for(j = 0;j<3;j++)          {              cout<<"b["<<i<<"]"<<"["<<j<<"] = ";              cin>>b[i][j];          }      }          for(i = 0;i<5;i++)          for(j = 0;j<5;j++)          {              for(k = 0;k<5;k++)              {                  t += a[i][k] * b[k][j];              }              c[i][j] = t;          }      cout<<"A矩阵与B矩阵的积为："<<endl;      for(i = 0;i<4;i++)      {          for(j = 0;j<3;j++)          {              cout<<setw(4)<<c[i][j];          }          cout<<endl;      }          return 0; }