c++经典代码大全(49页).doc

-c+经典代码大全-第 48 页#include <iostream.h> /包含iostream.h头文件main() /声明变量，并初始化 int a=010,b=10,c=0X10; /以十进制形式显示数据 cout<<"DEC:" cout<<" a="<<a; cout<<" b="<<b; cout<<" c="<<c<<endl; /以八进制形式显示数据 cout<<"OCT:" cout<<oct; /指定八进制输出 cout<<" a="<<a; cout<<" b="<<b; cout<<" c="<<c<<endl; /以十六进制形式显示数据 cout<<"HEX:" cout<<hex; /指定十六进制输出 cout<<" a="<<a; cout<<" b="<<b; cout<<" c="<<c<<endl; /八、十和十六进制数混合运算并输出 cout<<"a+b+c=" cout<<dec; /恢复十进制输出 cout<<a+b+c<<endl; /测试八、十和十六进制输入 cout<<"DEC:a=" cin>>a; cout<<"OCT:b=" cin>>b; cout<<"HEX:a=" cin>>c; cout<<"DEC:"<<dec<<endl; /指定十进制输出 cout<<"a="<<a<<endl; cout<<"b="<<b<<endl; cout<<"c="<<c<<endl; cin>>dx; cout<<"dy=" cin>>dy; cout<<dx<<"+"<<dy<<"="<<dx+dy<<endl; cout<<dx<<"-"<<dy<<"="<<dx-dy<<endl; cout<<dx<<"*"<<dy<<"="<<dx*dy<<endl; cout<<dx<<"/"<<dy<<"="<<dx/dy<<endl<<endl; /cout<<fx<<"%"<<fy<<"="<<fx%fy<<endl; Error! /测试float和double类型数据的有效位 fx=10.0;fy=6.0; float fz=fx/fy; dx=10.0;dy=6.0; double dz=dx/dy; cout<<"fz=" cout<<setprecision(20)<<fx<<"/"<<fy<<"="<<fz<<endl; cout<<"dz=" cout<<setprecision(20)<<dx<<"/"<<dy<<"="<<dz<<endl<<endl; /float型溢出 float x=3.5e14; cout<<"x="<<x<<endl; cout<<"x*x="<<x*x<<endl; cout<<"x*x*x="<<x*x*x<<endl;#include <iostream.h>main() /x,y 为操作数，c为运算符 int x,y,z; char c1; cin>>x>>c1>>y; /c1 /多路选择语句选择不同表达式计算语句 switch(c1) case '+':cout<<x<<"+"<<y<<"="<<x+y<<endl; break; case '-':cout<<x<<"-"<<y<<"="<<x-y<<endl; break; case '*':cout<<x<<"*"<<y<<"="<<x*y<<endl; break; case '/':cout<<x<<"/"<<y<<"="<<x/y<<endl; break; case '%':cout<<x<<"%"<<y<<"="<<x%y<<endl; break; default :cout<<"Wrong !"<<endl; /当不符合上述情况时执行本子句#include<iostream.h>float x=365.5; /声明全局变量main() int x=1,y=2; double w=x+y; double x=1.414,y=1.732,z=3.14; cout<<"inner:x="<<x<<endl; cout<<"inner:y="<<y<<endl; cout<<"inner:z="<<z<<endl; cout<<"outer:w="<<w<<endl; cout<<":x="<<:x<<endl; /访问重名的全局变量 cout<<"outer:x="<<x<<endl; cout<<"outer:y="<<y<<endl; cout<<"outer:w="<<w<<endl; /cout<<"inner:z="<<z<<endl;无效 cout<<":x="<<:x<<endl; /访问重名的全局变量#include<iostream.h>main() /显示1,2,3.10 for(int i=1;i<=10;i+) cout<<i<<" " cout<<endl; /显示10,9,8.1 for(int j=10;j>=1;j-) cout<<j<<" " cout<<endl; /显示1,3,5.9 for(int k=1;k<=10;k=k+2) cout<<k<<" " cout<<endl; /显示ABC.Z for(char c='A'c<='Z'c+) cout<<c; cout<<endl; /显示0,0.1,0.2.1.0 for(float x=0;x<=1.0;x=x+0.1) cout<<x<<" " cout<<endl; /显示0,0.1,0.2.1.0 for(float x1=0;x1<=1.0+0.1/2;x1=x1+0.1) cout<<x1<<" " cout<<endl; /计算s=1+2+3.+100 int s=0; for(int n=1;n<=100;n+) s=s+n; cout<<"s="<<s<<endl;#include<iostream.h>main() /计算s=1+2+3.+100 int s=0,n=1; while(n<=100) s=s+n; n+; cout<<"s="<<s<<endl; /累加键盘输入的数据 double x,sum=0.0; cout<<"x=" cin>>x; while(x!=0) sum+=x; cout<<"x=" cin>>x; cout<<"sum="<<sum<<endl;#include<iostream.h>main() /计算s=1+2+3.+100 int s=0,n=0; do n+; s+=n; while(n<100); cout<<"s="<<s<<endl; /累加键盘输入的数据 double x,sum=0.0; do cout<<"x=" cin>>x; sum+=x; while(x!=0); cout<<"sum="<<sum<<endl;#include<iostream.h>main() /计算和打印打印乘法九九表 for (int i=1;i<=9;i+) cout<<i; for (int j=1;j<=9;j+) cout<<'t'<<i<<"*"<<j<<"="<<i*j; cout<<endl;#include<iostream.h>main() int x,sum=0; /定义标号L1L1: cout<<"x=" cin>>x; if (x=-1) goto L2; /无条件转移语句，转到L2语句处 else sum+=x; goto L1; /无条件转移语句，转到L1语句处 /定义标号L2L2: cout<<"sum="<<sum<<endl;#include<iostream.h>main() /累加键盘输入的数据 double x,sum=0.0; while(1) cout<<"x=" cin>>x; if (x<=0) break; sum+=x; cout<<"sum="<<sum<<endl;#include<iostream.h>main() int i; for (i=1;i<=20;i+) if (i%3=0) /能被 3 整除的整数，返回进行下次循环 continue; cout<<i<<" " cout<<endl;#include<iostream.h>main() /声明数组和变量 int a5,i,sum; double avg; /从键盘上循环为数组赋值 for (i=0;i<5;i+) cout<<"a"<<i<<"=" cin>>ai; /直接显示数组元素 cout<<a0<<a1<<a2<<a3<<a4<<endl; /利用for循环显示数组各元素的值 for (i=0;i<5;i+) cout<<ai<<" " cout<<endl; /计算数组元素之和,并显示计算结果 sum=a0+a1+a2+a3+a4; cout<<"sum="<<sum<<endl; /利用循环计算数组的累加和 for (sum=0,i=0;i<5;i+) sum+=ai; /显示累加和及平均值 cout<<"sum="<<sum<<endl; avg=sum/5.0; cout<<"avg="<<avg<<endl;#include<iostream.h>main() int i,max,index,a5; /从键盘上为数组赋值 for (i=0;i<=4;i+) cout<<"a"<<i<<"=" cin>>ai; / 利用循环遍历数组，找出最大值的元素及其下标 max=a0; for (i=0;i<=4;i+) if (max<ai) max=ai; index=i; cout<<"nMax="<<max<<" index="<<index;#include<iostream.h>#define size 5main() /声明变量 int i,j; float t,asize; /从键盘上为数组赋值 for (i=0;i<size;i+) cout<<"a"<<i<<"=" cin>>ai; /对数组按从小到大顺序排序 for (i=0;i<size-1;i+) for (j=i+1;j<size;j+) if (ai>aj) t=ai; ai=aj; aj=t; /显示排序结果 for (i=0;i<size;i+) cout<<ai<<" " cout<<endl; /输入要查找的数据 int value; int found; /找到为1，否则为0 intlow,high,mid; for (i=1;i<=3;i+) cout<<"value=" cin>>value; /二分法查找数组a found=0; low=0; high=size-1; while(low<=high) mid=(high+low)/2; if (amid=value) found=1; break; if (amid<value) low=mid+1; else high=mid-1; if (found) cout<<"The valu found at:a"<<mid<<"="<<amid<<endl; else cout<<"The "<<value<<" is not found!"<<endl;#include<iostream.h>main()/声明变量 int i,j; float t,a5; /从键盘上为数组赋值 for (i=0;i<=4;i+) cout<<"a"<<i<<"=" cin>>ai; /对数组按从大到小顺序排序 for (i=0;i<=3;i+) for (j=i+1;j<=4;j+) if (ai<=aj) t=ai; ai=aj; aj=t; /显示排序结果 for (i=0;i<=4;i+) cout<<ai<<" "#include<iostream.h>main() /声明二维数组及变量 int a23,i,j; /从键盘上为数组a赋值 for (i=0;i<2;i+) for (j=0;j<3;j+) cout<<"a"<<i<<""<<j<<"=" cin>>aij; /显示数组a for (i=0;i<2;i+) for (j=0;j<3;j+) cout<<aij<<" " cout<<endl; /找出该数组的最大元素及其下标 int h,l,Max=a00; for (i=0;i<2;i+) for (j=0;j<3;j+) if (Max<aij) Max=aij; h=i; l=j; cout<<"Max:"<<"a"<<h<<""<<l<<"="<<ahl<<endl;#include<iostream.h>main() /声明字符数组和变量 char str6; int i; /从键盘上输入字符串 cout<<"str=" cin>>str; cout<<str<<endl; /按数组和下标变量两种方式显示字符数组 cout<<str<<endl; for (i=0;i<6;i+) cout<<stri; cout<<endl; /字符串反向输出 for (i=5;i>=0;i-) cout<<stri; cout<<endl; /将字符数组变成大写字母后输出 for (i=0;i<=5;i+) stri-=32; /小写字母转换成大写字母 cout<<str<<endl; /显示字符串#include<iostream.h>main() /声明变量和指针变量 int a,b,c,*ip; /指针变量ip指向变量a a=100; ip=&a; /使指针变量 ip 指向变量a cout<<"a="<<a<<endl; cout<<"*ip="<<*ip<<endl; cout<<"ip="<<ip<<endl; /指针变量ip指向变量b ip=&b; /使指针变量 ip 指向变量b b=200; cout<<"b="<<b<<endl; cout<<"*ip="<<*ip<<endl; cout<<"ip="<<ip<<endl; /指针变量ip指向变量c ip=&c; /使指针变量 ip 指向变量b *ip=a+b; cout<<"c="<<c<<endl; cout<<"*ip="<<*ip<<endl; cout<<"ip="<<ip<<endl;#include<iostream.h>main() /声明数组、变量和指针变量 int a23,i,j; int* ip; /从键盘上为数组a赋值 for (i=0;i<2;i+) /为数组a赋值 for (j=0;j<3;j+) cout<<"a"<<i<<""<<j<<"=" cin>>aij; /利用下标变量显示数组a for (i=0;i<2;i+) for (j=0;j<3;j+) cout<<aij<<" " cout<<endl; /利用指针变量显示数组a ip=&a00; for (i=0;i<2;i+) for (j=0;j<3;j+) cout<<"a"<<i<<""<<j<<"=" cout<<ip<<" " cout<<*ip<<endl; ip+;#include<iostream.h>main() /声明数组、变量和指针变量 int a=1,2,3,4,5,6; int *ip1,*ip2; /测试指针的赋值运算 ip1=a; ip2=ip1; cout<<"*ip1="<<(*ip1)<<endl; cout<<"*ip2="<<(*ip2)<<endl; /测试指针的自增自减运算和组合运算 ip1+; ip2+=4; cout<<"*ip1="<<(*ip1)<<endl; cout<<"*ip2="<<(*ip2)<<endl; /测试指针变量之间的关系运算 int n=ip2>ip1; cout<<"ip2>ip1="<<n<<endl; cout<<"ip2!=NULL="<<(ip2!=NULL)<<endl; /指针变量之间的减法 n=ip2-ip1; cout<<"ip2-ip1="<<n<<endl;#include<iostream.h>main() /声明字符型数组和指针变量 char str10; char *strip=str; /输入输出 cout<<"str=" cin>>str; /用字符数组输入字符串 cout<<"str="<<str<<endl; cout<<"strip="<<strip<<endl; cout<<"strip=" cin>>strip; /用字符指针变量输入字符串 cout<<"str="<<str<<endl; cout<<"strip="<<strip<<endl; /利用指针变量改变其指向字符串的内容 *(strip+2)='l' cout<<"str="<<str<<endl; cout<<"strip="<<strip<<endl; /动态为字符型指针变量分配内存 strip=new char(100); cout<<"strip=" cin>>strip; /用字符指针变量输入字符串 cout<<"str="<<str<<endl; cout<<"strip="<<strip<<endl;#include<iostream.h>main() / 声明用于存放运动员号码的数组 int h=1001,1002,1003,1004; / 声明用于存放运动员成绩的数组 float x=12.3,13.1,11.9,12.1; /声明用于存放运动姓名的字符型指针数组 char *p="Wang hua","Zhang jian","Li wei","Hua ming" /i,j,it是用做循环控制变量和临时变量 int i,j,it; /ft 用做暂存变量 float ft; /pt为字符型指针变量用做暂存指针变量 char *pt; /用选择法对数组x进行排序，并相应调整数组h和p中的数据 for (i=0;i<=3;i+) for (j=i+1;j<=3;j+) if (xi>=xj) ft=xi,xi=xj,xj=ft; it=hi,hi=hj,hj=it; pt=pi,pi=pj,pj=pt; /以下打印排序结果 for (i=0;i<=3;i+) cout<<hi<<" ,"<<pi<<" ,"<<xi<<endl;#include<iostream.h>main() /声明指针数组 char *colors="Red","Blue","Yellow","Green" /指向指针的指针变量 char *pt; /通过指向指针的变量访问其指向的内容 pt=colors; for (int i=0;i<=3;i+) cout<<"pt="<<pt<<endl; cout<<"*pt="<<*pt<<endl; cout<<"*pt="<<*pt<<endl; pt+;#include<iostream.h>main() /定义结构类型 struct books char title20; char author15; int pages; float price; /声明结构变量 struct books Zbk="VC+ ","Zhang",295,35.5; books Wbk; /对结构变量的输出 cout<<"Zbk:"<<endl; cout<<Zbk.title <<endl; cout<<Zbk.author<<endl; cout<<Zbk.pages<<endl; cout<<Zbk.price<<endl; cout<<"-"<<endl; /对结构成员的运算 Zbk.pages+=10; Zbk.price+=0.5; cout<<"Zbk.pages="<<Zbk.pages<<endl; cout<<"Zbk.price="<<Zbk.price<<endl; cout<<"-"<<endl; /对结构变量的输入输出 cout<<"Wbk.title =" cin>>Wbk.title; cout<<"Wbk.author=" cin>>Wbk.author; cout<<"Wbk.pages=" cin>>Wbk.pages; cout<<"Wbk.price=" cin>>Wbk.price; cout<<"Wbk:"<<endl; cout<<Wbk.title <<endl; cout<<Wbk.author<<endl; cout<<Wbk.pages<<endl; cout<<Wbk.price<<endl; cout<<"-"<<endl; /结构变量之间的相互赋值 books temp; temp=Wbk; cout<<"temp:"<<endl; cout<<temp.title<<endl; cout<<temp.author<<endl; cout<<temp.pages<<endl; cout<<temp.price<<endl;#include<iostream.h>main() int i; /定义结构类型 struct student int num; char name10; float maths; float physics; float chemistry; double total; /声明结构数组st student st3; /从键盘上为结构数组输入值 cout<<" num name maths physics chemistry "<<endl; for (i=0;i<3;i+) cout<<i+1<<" " cin>>sti.num; cin>>sti.name; cin>>sti.maths; cin>>sti.physics; cin>>sti.chemistry; /计算每个学生的总成绩 for (i=0;i<3;i+) sti.total=sti.maths+sti.physics+sti.chemistry; /输出结构数组各元素的值 for (i=0;i<3;i+) cout<<"st"<<i<<": " cout<<sti.num<<'t' cout<<sti.name<<'t' cout<<sti.maths<<'t' cout<<sti.physics<<'t' cout<<sti.chemistry<<'t' cout<<sti.total<<endl;#include<iostream.h>main() /定义结构类型 struct human char name10; int sex; int age; /声明结构变量和结构指针变量,并初始化 struct human x="WangPing",1,30,*p=NULL; /结构指针变量指向对象 p=&x; /显示结构变量的值 cout<<"x.name="<<x.name<<endl; cout<<"x.sex="<<x.sex<<endl; cout<<"x.age="<<x.age<<endl; /利用结构指针显示结构对象中的数据 cout<<"(*p).name="<<(*p).name<<endl; cout<<"(*p).sex="<<(*p).sex<<endl; cout<<"(*p).age="<<(*p).age<<endl; cout<<"p->name="<<p->name<<endl; cout<<"p->sex="<<p->sex<<endl; cout<<"p->age="<<p->age<<endl; /通过结构指针为结构对象输入数据 cout<<"name:" cin>>(*p).name; cout<<"sex:" cin>>(*p).sex; cout<<"age:" cin>>(*p).age; /显示结构变量的值 cout<<"x.name="<<x.name<<endl; cout<<"x.sex="<<x.sex<<endl; cout<<"x.age="<<x.age<<endl;include<iostream.h>main() /定义结构类型 struct human char name10; int sex; int age; /声明结构变量和结构指针,并初始化 struct human x="WangPing",1,30,*p=&x; /利用结构指针显示结构中的数据 cout<<"(*p).name="<<(*p).name<<endl; cout<<"(*p).sex="<<(*p).sex<<endl; cout<<"(*p).age="<<(*p).age<<endl; cout<<"-