add exercice2

TP/1-ProceduralProgramming/exercice2.cpp

+#include <iostream>
+#include <cmath> // for std::round
+
+
+//! Returns `number` * (2 ^ `exponent`) 
+int times_power_of_2(int number, int exponent)
+{
+    while (exponent > 0)
+    { 
+        number *= 2; 
+        exponent -= 1; 
+    }
+    while (exponent < 0)
+    { 
+        number /= 2;
+        exponent += 1 ; 
+    }
+    
+    return number;
+}
+    
+
+//! Round to `x` the nearest integer.
+int round_as_int(double x)
+{
+    return static_cast<int>(std::round(x));
+}
+
+
+
+/************************************/
+// Main function
+/************************************/
+
+int main(int argc, char** argv)
+{
+    static_cast<void>(argc); // to silence warning about unused argc - don't bother 
+    static_cast<void>(argv); // to silence warning about unused argv - don't bother 
+        
+    int numerator1 = round_as_int(0.65 * times_power_of_2(1, 1));
+    std::cout << "0.65 ~ " << numerator1 << " / 2^1" << std::endl ;
+  
+    int numerator2 = round_as_int(0.65 * times_power_of_2(1, 2));
+    std::cout << "0.65 ~ " << numerator2 << " / 2^2" << std::endl ;
+  
+    int numerator3 = round_as_int(0.65 * times_power_of_2(1, 3));
+    std::cout << "0.65 ~ " << numerator3 << " / 2^3" << std::endl ;
+  
+    std::cout << std::endl ;
+    
+    return EXIT_SUCCESS;
+}
+