1.
#include <iostream> #include <fstream> #include <ctime> #include "vector.h" int main() { using namespace std; using VECTOR::Vector; ofstream of; of.open("result.txt"); srand(time(0)); double direction; Vector step; Vector result(0.0,0.0); unsigned int steps = 0; double target; double dstep; cout <<"Enter target distance ( q to quit ): "; cin >> target; cout << "Enter step length: "; cin >> dstep; of << "Target Distance : " << target << ", Step Size: " << dstep << endl; for(steps = 0; result.magval() < target; steps++) { direction = rand() % 360; step.reset (dstep, direction, Vector::POL); result = result + step; of << steps << ": "<< result << endl; } of << "After " << steps << " steps, the subject has the following location: "; of << result <<endl; result.polar_mode(); of << " or " << result << endl; of << "Average outward distance per step = " << result.magval()/steps << endl; steps = 0; result.reset(0.0, 0.0); cout << "Bye! "; cin.clear(); while(cin.get() != ' ') continue; of.close(); return 0; }
======================================== 答案 =========================================
#include <iostream> #include <fstream> #include <limits> #include "TVector.h" using namespace std; using namespace n_vector; int main (void) { ofstream of; of.open("output.txt"); while (true) { double setp; double distance; unsigned cnt_steps = 0; cout << "输入步长:"; cin >> setp; if (!cin || setp <= 0) { break; } cin.clear(); // 清空输入缓冲区错误标志位 cin.ignore(std::numeric_limits<std::streamsize>::max(), ' '); // 清空输入缓冲区内容 cout << "输入距离:"; cin >> distance; if (!cin || distance <= 0) { break; } cin.clear(); // 清空输入缓冲区错误标志位 cin.ignore(std::numeric_limits<std::streamsize>::max(), ' '); // 清空输入缓冲区内容 of << "开始>>>>>>>>>>" << endl; TVector vec(0, 0, TVector::POL); srand((unsigned)time(nullptr)); while (vec.getLength() < distance) { vec += TVector(setp, rand()%361, TVector::POL); of << cnt_steps++ << ":" << vec << endl; } of << "结束<<<<<<<<<<" << endl; of << "距离" << distance << ",步长" << setp << ",历经" << cnt_steps << "步走完,终点坐标" << vec << endl; of << "========== " << endl; } of.close(); cout << endl; return (0); }
2.答案
double setp;
double distance;
int times;
int max_setps = 0;
int min_setps = numeric_limits<unsigned>::max();
int sum_setps = 0;
......
for (int i = 0; i < times; ++i) { int cnt_steps = 0; TVector vec(0, 0, TVector::POL); cout << i << ":"; while (vec.getLength() < distance) { vec += TVector(setp, rand()%360, TVector::POL); ++cnt_steps; } cout << cnt_steps << "steps to " << vec << endl; if (cnt_steps > max_setps) { max_setps = cnt_steps; // get max step } if (cnt_steps < min_setps) { min_setps = cnt_steps; // get min step } sum_setps += cnt_steps; // total steps }
7. 11_7_complex0.h
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
#ifndef E11_7_COMPLEX0_H #define E11_7_COMPLEX0_H #include <iostream> class Complex { private: double m_a; double m_c; public: Complex(); //default constructor ~Complex(); Complex(double x1, double y1 ); // constructor //operator overloading Complex operator+(const Complex & t) const; Complex operator-(const Complex & t) const; Complex operator*(double n) const; Complex operator*(const Complex & t) const; Complex operator~() const; //friend friend std::ostream & operator<<(std::ostream & os, const Complex & v); friend std::istream & operator>>(std::istream & is, Complex & t); friend Complex operator*(double m, const Complex & t); }; #endif //E11_7_COMPLEX0_H
11_7_comlpex0.cpp
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
#include "complex0.h" using std::endl; Complex::Complex() { m_a = m_c = 0.0; } Complex::~Complex() {} Complex::Complex(double x1, double y1) { m_a = x1; m_c = y1; } Complex Complex::operator+(const Complex &t) const { return Complex(t.m_a + m_a, t.m_c + m_c); } Complex Complex::operator-(const Complex & t) const { return Complex(m_a - t.m_a, m_c - t.m_c); } Complex Complex::operator*(double n) const { return Complex(m_a * n, m_c * n); } Complex Complex::operator*(const Complex & t) const { return Complex(t.m_a * m_a - t.m_c * m_c, t.m_c * m_a + t.m_a * m_c); } Complex Complex::operator~() const { return Complex(m_a, -m_c); } //friend std::ostream &operator<<(std::ostream & os, const Complex & v) { os << "( " << v.m_a <<", " << v.m_c <<"i )" << endl; } std::istream &operator>>(std::istream & is, Complex & t) { std::cout << "Real: "; is >> t.m_a; std::cout << "Imaginary: "; is >> t.m_c; } Complex operator*(double m, const Complex & t) { return Complex(t.m_a * m, t.m_c * m); }
11_7_main.cpp
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
#include <iostream> using namespace std; #include "complex0.h" int main() { Complex a(3.0, 4.0); Complex c; cout << "Enter a complex number (q to quit): "; while (cin >> c) { cout << "c is " << c << ' '; cout << "complex conjugate is " << ~c << ' '; cout << "a is " << a << ' '; cout << "a + c is " << a + c << ' '; cout << "a - c is " << a - c << ' '; cout << "a * c is " << a * c << ' '; cout << "2 * c is " << 2 * c << ' '; cout << "Enter a complex number ( q to quit): "; } cout << "Done! "; return 0; }