What do we need to use when we have multiple subscripts?
What do we need to do to pointer for overloading the subscript operator?
What is the output of this program?
1.
#include
2.
using namespace std;
3.
class sample
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{
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private:
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int* i;
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int j;
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public:
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sample (int j);
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~sample ();
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int& operator [] (int n);
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};
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int& sample::operator [] (int n)
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{
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return i[n];
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}
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sample::sample (int j)
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{
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i = new int [j];
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j = j;
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}
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sample::~sample ()
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{
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delete [] i;
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}
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int main ()
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{
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sample m (5);
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m [0] = 25;
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m [1] = 20;
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m [2] = 15;
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m [3] = 10;
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m [4] = 5;
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for (int n = 0; n < 5; ++ n)
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cout << m [n];
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return 0;
37.
}
What is the output of this program?
1.
#include
2.
using namespace std;
3.
class A
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{
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public:
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int x;
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A(int n = 0) : x(n) {};
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int& operator[](int n)
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{
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cout << "0" ;
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return x;
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}
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int operator[](int n) const
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{
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cout << "1" ;
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return x;
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}
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};
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void foo(const A& a)
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{
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int z = a[2];
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}
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int main()
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{
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A a(7);
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a[3] = 8;
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int z = a[2];
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foo(a);
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return 0;
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}
What is the output of this program?
1.
#include
2.
using namespace std;
3.
const int limit = 4;
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class safearray
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{
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private:
7.
int arr[limit];
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public:
9.
int& operator [](int n)
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{
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if (n == limit - 1)
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{
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int temp;
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for (int i = 0; i < limit; i++)
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{
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if (arr[n + 1] > arr[n])
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{
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temp = arr[n];
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arr[n] = arr[n + 1];
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arr[n + 1] = temp;
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}
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}
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}
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return arr[n];
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}
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};
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int main()
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{
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safearray sa1;
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for(int j = 0; j < limit; j++)
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sa1[j] = j*10;
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for(int j = 0; j < limit; j++)
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{
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int temp = sa1[j];
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cout << "Element " << j << " is " << temp;
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}
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return 0;
38.
}