27 lines
467 B
C++
27 lines
467 B
C++
// 设计一个Circle类，有数据成员radius（半径）、成员函数area()，计算圆的面积。构造一个Circle对象进行测试。
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#include <bits/stdc++.h>
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using namespace std;
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class Circle {
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private:
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double radius;
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public:
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void setRadius(double r) { radius = r; }
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double area() { return M_PI * radius * radius; }
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};
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int main() {
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Circle c;
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double r;
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cin >> r;
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c.setRadius(r);
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cout << "Area of circle: " << c.area() << endl;
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return 0;
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} |