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//座标的两种表标方法的转换#include<iostream>#include<cmath>struct polar{double distance;double angle;};struct rect{double x;double y;};polar rectToPolar(rect xypos);void showPolar(polar dapos);int main(){using namespace std;rect rplace;polar pplace;cout << "Enter the x and y value : ";while(cin >> rplace.x >> rplace.y){pplace = rectToPolar( rplace );showPolar( pplace );cout << "Next two numbers(q to quit): ";}cout << "-DONE-" << endl;return 0;}polar rectToPolar(rect xy){using namespace std;polar answer;answer.distance = sqrt(xy.x*xy.x+xy.y*xy.y);answer.angle = atan2(xy.y, xy.x);return answer;}void showPolar(polar dapos){using namespace std;const double red_to_deg = 57.29577951;cout << "distance = " << dapos.distance<< ". angle = " << dapos.angle * red_to_deg<<" degrees/n";}