CPP Sample Questions Answers

What happens when you attempt to compile and run the following code?

#include

#include

#include

using namespace std;

templatestruct Out {

ostream & out;

Out(ostream & o): out(o){}

void operator()(const T & val ) {

out<

}

};

struct Sequence {

int start;

Sequence(int start):start(start){}

int operator()() {

return start++ ; }};

int main() {

vector v1(10);

generate(v1.rbegin(), v1.rend(), Sequence(1));

rotate(v1.begin(),v1.begin() + 1, v1.end() );

for_each(v1.begin(), v1.end(), Out(cout) );cout<

return 0;

}

Program outputs:

What will happen when you attempt to compile and run the following code?

#include

#include

#include

using namespace std;

int main ()

{

vectorv1;

dequed1;

for(int i=0; i<5; i++)

{

v1.push_back(i);v1.push_front(i);

d1.push_back(i);d1.push_front(i);

}

for(int i=0; i

{

cout<

}

cout<

return 0;

}

What will be its output:

What happens when you attempt to compile and run the following code?

#include

#include

#include

#include

using namespace std;

templatestruct Out {

ostream & out;

Out(ostream & o): out(o){}

void operator() (const T & val ) { out<

int main() {

int t[]={8, 10, 5, 1, 4, 6, 2, 7, 9, 3};

deque d1(t, t+10);

set s1(t,t+10);

cout<

return 0;

}

Choose all possible outputs (all that apply):

What happens when you attempt to compile and run the following code?

#include

#include

#include

#include

#include

using namespace std;

struct display {

void operator() (int i) {cout << " " << i;}

};

int main() {

int t[] = { 10, 5, 9, 6, 2, 4, 7, 8, 3, 1 };

vector v1(t, t + 10);

deque d1(t, t + 10);

set s1(t, t + 10);

for_each(v1.begin(), v1.end(), display); //Line I

for_each(d1.begin(), d1.end(), *(new display())); // Line II

for_each(s1.begin(), s1.end(), display()); // Line III

return 0;

}

What happens when you attempt to compile and run the following code?

#include

using namespace std;

int main()

{

cout<

return 0;

}

Program outputs:

What happens when you attempt to compile and run the following code?

#include

#include

using namespace std;

template

class A {

T_v;

public:

A() {}

A(T v): _v(v){}

T getV() { return _v; }

void add(T & a) { _v+=a; }

void add(string & a) {

_v.insert(0, a);

}

};

int main()

{

Aa("Hello");

string s(" world!");

a.add(s);

cout << a.getV() <

return 0;

}

What happens when you attempt to compile and run the following code?

#include

#include

#include

#include

using namespace std;

int main(){

int second[] ={ 3, 4, 2, 1, 6, 5, 7, 9, 8, 0 };

string first[] = {"three", "four", "two", "one", "six","five", "seven", "nine","eight","zero"};

map m;

for(int i=0; i<10; i++) {

m.insert(pair(second[i],first[i]));

}

m[0]="ten";

m.insert(pair(1,"eleven"));

for(map::iterator i=m.begin();i!= m.end(); i++) {

cout<second<<" ";

}

return 0;

}

What happens when you attempt to compile and run the following code?

#include

#include

#include

using namespace std;

templatestruct Out {

ostream & out;

Out(ostream & o): out(o){}

void operator() (const T & val ) { out<

int main() {

int t[]={8, 10, 5, 1, 4, 6, 2, 7, 9, 3};

deque d1(t, t+10);

deque::iterator it = lower_bound(d1.begin(), d1.end(), 4);

for_each(it, d1.end(), Out(cout));cout<

return 0;

}

Program outputs:

What happens when you attempt to compile and run the following code?

#include

#include

#include

#include

using namespace std;

templatestruct Out {

ostream & out;

Out(ostream & o): out(o){}

void operator() (const T & val ) { out<

};

bool Compare(char a, char b) { return tolower(a) < tolower(b);}

int main() {

char s[]={"qwerty"};

char t1[]={"ert"};

char t2[]={"ERT"};

sort(s, s+6);

cout<

return 0;

}

Program outputs:

What happens when you attempt to compile and run the following code?

#include

#include

using namespace std;

int main() {

int t[] = { 1, 1, 2, 2, 3, 3, 4, 4, 5, 5 };

string s[] = { "one", "one", "two", "two", "three","three", "four", "four", "five", "five"};

map m;

for (int i = 0; i < 10; i++) {

m.push_back(pair(t[i], s[i]));

}

for (map::iterator i = m.begin(); i != m.end(); i++) {

cout << i?>first << " ";

}

return 0;

}

What will happen when you attempt to compile and run the code below, assuming that you enter the following sequence: true false?

#include

#include

using namespace std;

int main ()

{

bool a,b;

cin>>boolalpha>>a>>b;

cout<

return 0;

}

Program will output:

What happens when you attempt to compile and run the following code?

#include

#include

#include

#include

#include

using namespace std;

class compare {

bool reverse;

public:

compare(bool revparam = false){ reverse = revparam;}

bool operator()(int lhs, int rhs) const{

if (reverse)return (lhs > rhs);

elsereturn (lhs < rhs);

}

};

int main(){

int myints[] ={ 3, 4, 2, 1, 6, 5, 7, 9, 8, 0 };

priority_queue > first(myints, myints + 10);

priority_queue, compare> second(myints, myints + 10,

compare(false));

while (first.size() > 0){

cout << first.top() << " "; first.pop();

}

while (second.size() > 0) {

cout << second.top() << " ";second.pop();

}

return 0;

}

Which sentence is correct about the code below?

#include

#include

#include

using namespace std;

class A {

int a;

public:

A(int a) : a(a) {}

int getA() const { return a; }

void setA(int a) { this?>a = a; }

/* Insert Code Here */

};

struct add10 { void operator()(A & a) { a.setA(a.getA() + 10); } };

int main() {

int t[] = { 10, 5, 9, 6, 2, 4, 7, 8, 3, 1 };

vector v1(t, t + 10);

for_each(v1.begin(), v1.end(), add10());

vector::iterator it = find(v1.begin(), v1.end(), A(7));

cout << it?>getA() << endl;

return 0;

}

What happens when you attempt to compile and run the following code?

#include

#include

#include

using namespace std;

class B { int val;

public:

B(int v):val(v){}

int getV() const {return val;} bool operator < (const B & v) const { return val

ostream & operator <<(ostream & out, const B & v) { out<

templatestruct Out {

ostream & out;

Out(ostream & o): out(o){}

void operator() (const T & val ) { out<

int main() {

int t[]={8, 10, 5, 1, 4, 6, 2, 7, 9, 3};

vector v1(t, t+10);

sort(v1.begin(), v1.end());

for_each(v1.begin(), v1.end(), Out(cout));cout<

return 0;

}

Program outputs: