Assignment #
What will be the output ?
#include <iostream>
using namespace std;
void swap(char *x, char *y)
{
char *t = x;
x = y;
y = t;
}
int main()
{
char *x = "geeksquiz";
char *y = "geeksforgeeks";
char *t;
swap(x, y);
cout << x << " " << y;
t = x;
x = y;
y = t;
cout << " " << x << " " << y;
return 0;
}
Options
a. geeksforgeeks geeksquiz geeksforgeeks geeksquiz
b. geeksquiz geeksforgeeks geeksquiz geeksforgeeks
c. geeksquiz geeksforgeeks geeksforgeeks geeksquiz
d. Compiler Error
Correct Answer
c. geeksquiz geeksforgeeks geeksforgeeks geeksquiz
The function changes only values of the formal parameters, and does not affect the value stored at the address.
What will be the output ?
#include <iostream>
using namespace std;
int main()
{
float arr[5] = {12.5, 10.0, 13.5, 90.5, 0.5};
float *ptr1 = &arr[0];
float *ptr2 = ptr1 + 3;
cout<<*ptr2<<" ";
cout<< ptr2 - ptr1;
return 0;
}
Options
a. 90.5 3
b. 90.5 12
c. 10.0 12
d. undefined
Correct Answer
a. 90.5 3
Basic arithmetic.
What will be the output ?
#include<iostream>
using namespace std;
int main() {
char st[] = "ABCD";
for(int i = 0; st[i] != ‘\0’; i++) {
cout << st[i] << *(st)+i << *(i+st) << i[st];
}
return 0;
}
Options
a. AAAABBBBCCCCDDDD
b. ABCD
c. A65AAB66BBC67CCD68DD
d. Compilation Error
Correct Answer
c. A65AAB66BBC67CCD68DD
st[i] = *(st+i) = *(i+st)
while *(st)+i = ASCII_value + i
What will be the output ?
#include <iostream>
using namespace std;
void Q(int z)
{
z += z;
cout<<z << " ";
}
void P(int *y)
{
int x = *y + 2;
Q(x);
*y = x - 1;
cout<<x << " ";
}
int main()
{
int x = 5;
P(&x);
cout<<x;
return 0;
}
Options
a. 7 6 14
b. 14 7 5
c. 14 7 6
d. 14 6 5
Correct Answer
c. 14 7 6
Basics, do on pen and paper if need be.
What will be the output ?
#include<iostream>
using namespace std;
int main()
{
int ***r, **q, *p, i=8;
p = &i;
(*p)++;
q = &p;
(**q)++;
r = &q;
cout<<*p << " " <<**q << " "<<***r;
return 0;
}
Options
a. 8 8 8
b. 10 10 10
c. 9 10 11
d. 9 10 10
Correct Answer
b. 10 10 10
Basics, just draw a diagram.
What will be the output ?
int f(int x, int *py, int **ppz)
{
int y, z;
**ppz += 1;
z = **ppz;
*py += 2;
y = *py;
x += 3;
return x + y + z;
}
int main()
{
int c, *b, **a;
c = 4;
b = &c;
a = &b;
cout << f(c, b, a);
return 0;
}
Options
a. 21
b. 18
c. 19
d. 24
Correct Answer
c. 19
Basics, just draw a diagram. Make new memory for formal variables.