C Plus Plus Miscellaneous - Study Mode
[#626] What will be the output of the following C++ code? #include <iostream>
#include <complex>
using namespace std
int main()
{
complex <double> cn(3.0, 5.0)
cout<<"Complex number is: "<<real(cn)<<" + "<<imag(cn)<<"i"<<endl
return 0
}
Correct Answer
(A) Complex number is: 3 + 5i
Explanation
Solution: In the given C++ code, the complex class from the C++ Standard Library is used to represent a complex number. In the statement complex cn(3.0, 5.0) , the constructor initializes the real part as 3.0 and the imaginary part as 5.0 . The function real(cn) returns the real part of the complex number, which is 3 . The function imag(cn) returns the imaginary part, which is 5 . Hence, the output will be: Complex number is: 3 + 5i .
[#627] What will be the output of the following C++ code? #include <iostream>
using namespace std
class poly
{
protected:
int width, height
public:
void set_values(int a, int b)
{
width = a
height = b
}
}
class Coutput
{
public:
void output(int i)
}
void Coutput::output(int i)
{
cout << i
}
class rect:public poly, public Coutput
{
public:
int area()
{
return(width * height)
}
}
class tri:public poly, public Coutput
{
public:
int area()
{
return(width * height / 2)
}
}
int main()
{
rect rect
tri trgl
rect.set_values(3, 4)
trgl.set_values(4, 5)
rect.output(rect.area())
trgl.output(trgl.area())
return 0
}
Correct Answer
(B) 1210
[#628] What will be the output of the following C++ code? #include <iostream>
#include <map>
using namespace std
int main ()
{
map<char, int> mymap
map<char, int> :: iterator it
mymap['b'] = 100
mymap['a'] = 200
mymap['c'] = 300
for (map<char, int> :: iterator it = mymap.begin()
it != mymap.end()
++it)
cout << it -> first << " => " << it -> second << '
'
return 0
}
Correct Answer
(C) a => 200 b => 100 c => 300
[#629] What will be the output of the following C++ code? #include <iostream>
#include <deque>
using namespace std
int main ()
{
unsigned int i
deque<int> mydeque
deque<int> :: iterator it
mydeque.push_back ( 100 )
mydeque.push_back ( 200 )
mydeque.push_back ( 300 )
for (it = mydeque.begin()
it != mydeque.end()
++it)
mydeque.clear()
cout << ' ' << *it
}
Correct Answer
(D) error
[#630] What will be the output of the following C++ code? #include <iostream>
#include <algorithm>
#include <vector>
using namespace std
bool myfunction (int i,int j)
{
return (i < j)
}
int main ()
{
int myints[] = {9, 8, 7, 6}
vector<int> myvector (myints, myints + 4)
partial_sort (myvector.begin(), myvector.begin() + 2, myvector.end())
partial_sort (myvector.begin(), myvector.begin() + 2, myvector.end(),
myfunction)
for (vector<int> :: iterator it = myvector.begin()
it != myvector.end()
++it)
cout << ' ' << *it
return 0
}
Correct Answer
(C) 6 7 9 8