39 lines
888 B
C++
39 lines
888 B
C++
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//error2.cpp -- returning an error code
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#include <iostream>
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#include <cfloat> // (or float.h) for DBL_MAX
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bool hmean(double a, double b, double * ans);
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int main()
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{
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double x, y, z;
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std::cout << "Enter two numbers: ";
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while (std::cin >> x >> y)
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{
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if (hmean(x,y,&z))
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std::cout << "Harmonic mean of " << x << " and " << y
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<< " is " << z << std::endl;
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else
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std::cout << "One value should not be the negative "
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<< "of the other - try again.\n";
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std::cout << "Enter next set of numbers <q to quit>: ";
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}
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std::cout << "Bye!\n";
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return 0;
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}
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bool hmean(double a, double b, double * ans)
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{
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if (a == -b)
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{
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*ans = DBL_MAX;
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return false;
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}
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else
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{
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*ans = 2.0 * a * b / (a + b);
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return true;
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}
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}
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