Thanks ______ telling me that[ ]
A. of
B. for
C. with
D. at
答案：B
如图是某同学用频闪照相研究平抛运动时拍下的照片，背景方格纸的边长为2.5cm，A、B、C是同一小球在频闪照相中拍下的三个连续的不同位置时的照片，则：（g=10m/s2）
①频闪照相相邻闪光的时间间隔______s；
②小球水平抛出的初速度v0=______m/s；
③小球经过B点时其竖直分速度大小为vBy=______m/s．
【说明】软件设计师东方飞龙利用UML设计了一个迷你小型复数类，其类图如图13-11所示。
【代码13-l】 /*___________________________________*/ /********* 文件 MiniComplex. h*********/ /*___________________________________*/ #include＜iostream＞ using namespace std; class MiniComplex { (1) ： //重载流插入和提取运算符 (2) ostream & operator ＜＜(ostream & osObject, const MiniComplex & complex) { osObject ＜＜"("＜＜complex. realPart＜＜"+"＜＜complex. imagPart ＜＜"I"＜＜")"； return osObject； } friend (3) operator ＞＞(istream & isObject, MiniComplex & complex) { char ch; isObject ＞＞complex. realPart ＞＞ch＞＞complex. imagPart ＞＞ch; return isObject； } MiniComplex(double real=0, double imag=0)； //构造函数 MiniComplex operator+(const MiniComplex & otherComplex)const! //重载运算符+ MiniComplex operator--(const MiniComplex & otherComplex)const! //重载运算符- MiniComplex operator*(const MiniComplex& othmComplex)const； //重载运算符* MiniComplex operator/(const MiniComplex & otherComplex)const； //重载运算符/ bool operator==(const MiniComplex &otherComplex)const； //重载运算符== private： double realPart； //存储实部变量 double imagPart； //存储虚部变量 }; /*_______________________________________________________*/ /* * * * * * * * *文件 MiniComplex. cpp* * * * * * * * * */ /*_______________________________________________________*/ # include "MiniComplex.h" bool MiniComplex:: operator==(const MiniComplex & otherComplex)const { (1) ;} MiniComplex:: MiniComplex(double real, double imag){realPart=real;imagPart=imag!} MiniComplex MiniComplex:: operator+(const MiniComplex & otherComplex)const { MiniComplex temp; temp. realPart=realPart+ otherComplex. realPart; temp. imagPart=imagPart+ otherComplex. imagPart; return temp； } MiniComplex MiniComplex::operator--(const MiniComplex & otherComplex)const { MiniComplex temp; temp.realPart=realPart-otherComplex.realPart； temp. imagPart=imagPart-otherCompler.imagPart； return temp； } MiniComplex MiniComplex:: operator*(const MiniComplex& otherComplex)const { MiniComplex temp； temp.realPart=(realPart* otherComplex.realPart)-(imag-Part* otherComplex.imag-Part); temp imagPart=(realPart* otherComplex. imagPart)+(imag-Part *otherComplex.realPart); return temp， } MiniComplex MiniComplex:: operator/(const MiniComplex& otherComplex)eonst { MiniComplex temp; float tt; tt=1/(otherComplex. realPart *otherComplex. realPart+otherComplex. imagPart* other Complex.imagPart)； temp. realPart=((realPart* otherComplex.realPart)+(imagPart* otherComplex.imagPart))*tt; temp. imagPart=((imagPart * otherComplex.realPart)-(realPart* otherComplex.imagPart))*tt; return temp； } /*__________________________________________________*/ /* * * * * * * *主函数所在文件main.cpp* * * * * * * */ /*_________________________________________________*/ # include＜iostream＞ # include " (5) " using namespace std; int main(void) { MiniComplex num1(23, 34), num2; cin＞＞num2； cout＜＜"Initial Value of Numl="＜＜num1＜＜"\nInitial Value of Num2="＜＜num2＜＜end1; cout＜＜num1＜＜"+"＜＜num2＜＜"="＜＜num1+num2＜＜end1； //使用重载的加号运算符 cout＜＜num1＜＜"-"＜＜num2＜＜"="＜＜num1-num2＜＜end1; //使用重载的减号运算符 cout＜＜num1＜＜"*"＜＜num2＜＜"-"＜＜num1*num2＜＜end1; //使用重载的乘号运算符 cout＜＜num1＜＜"/"＜＜num2＜＜"="＜＜num1/num2＜＜end1； //使用重载的除号运算符 return 0; }
【代码13-l】 /*___________________________________*/ /********* 文件 MiniComplex. h*********/ /*___________________________________*/ #include＜iostream＞ using namespace std; class MiniComplex { (1) ： //重载流插入和提取运算符 (2) ostream & operator ＜＜(ostream & osObject, const MiniComplex & complex) { osObject ＜＜"("＜＜complex. realPart＜＜"+"＜＜complex. imagPart ＜＜"I"＜＜")"； return osObject； } friend (3) operator ＞＞(istream & isObject, MiniComplex & complex) { char ch; isObject ＞＞complex. realPart ＞＞ch＞＞complex. imagPart ＞＞ch; return isObject； } MiniComplex(double real=0, double imag=0)； //构造函数 MiniComplex operator+(const MiniComplex & otherComplex)const! //重载运算符+ MiniComplex operator--(const MiniComplex & otherComplex)const! //重载运算符- MiniComplex operator*(const MiniComplex& othmComplex)const； //重载运算符* MiniComplex operator/(const MiniComplex & otherComplex)const； //重载运算符/ bool operator==(const MiniComplex &otherComplex)const； //重载运算符== private： double realPart； //存储实部变量 double imagPart； //存储虚部变量 }; /*_______________________________________________________*/ /* * * * * * * * *文件 MiniComplex. cpp* * * * * * * * * */ /*_______________________________________________________*/ # include "MiniComplex.h" bool MiniComplex:: operator==(const MiniComplex & otherComplex)const { (1) ;} MiniComplex:: MiniComplex(double real, double imag){realPart=real;imagPart=imag!} MiniComplex MiniComplex:: operator+(const MiniComplex & otherComplex)const { MiniComplex temp; temp. realPart=realPart+ otherComplex. realPart; temp. imagPart=imagPart+ otherComplex. imagPart; return temp； } MiniComplex MiniComplex::operator--(const MiniComplex & otherComplex)const { MiniComplex temp; temp.realPart=realPart-otherComplex.realPart； temp. imagPart=imagPart-otherCompler.imagPart； return temp； } MiniComplex MiniComplex:: operator*(const MiniComplex& otherComplex)const { MiniComplex temp； temp.realPart=(realPart* otherComplex.realPart)-(imag-Part* otherComplex.imag-Part); temp imagPart=(realPart* otherComplex. imagPart)+(imag-Part *otherComplex.realPart); return temp， } MiniComplex MiniComplex:: operator/(const MiniComplex& otherComplex)eonst { MiniComplex temp; float tt; tt=1/(otherComplex. realPart *otherComplex. realPart+otherComplex. imagPart* other Complex.imagPart)； temp. realPart=((realPart* otherComplex.realPart)+(imagPart* otherComplex.imagPart))*tt; temp. imagPart=((imagPart * otherComplex.realPart)-(realPart* otherComplex.imagPart))*tt; return temp； } /*__________________________________________________*/ /* * * * * * * *主函数所在文件main.cpp* * * * * * * */ /*_________________________________________________*/ # include＜iostream＞ # include " (5) " using namespace std; int main(void) { MiniComplex num1(23, 34), num2; cin＞＞num2； cout＜＜"Initial Value of Numl="＜＜num1＜＜"\nInitial Value of Num2="＜＜num2＜＜end1; cout＜＜num1＜＜"+"＜＜num2＜＜"="＜＜num1+num2＜＜end1； //使用重载的加号运算符 cout＜＜num1＜＜"-"＜＜num2＜＜"="＜＜num1-num2＜＜end1; //使用重载的减号运算符 cout＜＜num1＜＜"*"＜＜num2＜＜"-"＜＜num1*num2＜＜end1; //使用重载的乘号运算符 cout＜＜num1＜＜"/"＜＜num2＜＜"="＜＜num1/num2＜＜end1； //使用重载的除号运算符 return 0; }