Question

(C++ Algorithms) Given the following function declarations, write the definitions according to the specifications of each.

All of the algorithms you are being asked to implement operate on pointer ranges. A *pointer range* is a pair of pointers referring to a sequence of objects. For example:

int a[] = {1, 2, 3, 4, 5};
int* first = a + 1;
int* limit = first + 3;

Here, first and limit are pointers to objects in or past the end of a. In a pointer range, the limit pointer is always considered to point past the last element of the range. The range does not include the object pointed to by limit. In fact, we commonly denote ranges using the mathematical interval notation. The expression [first, limit) denotes the sequence of objects starting at first and up to but not including limit

Example Function Definition

// print outputs the value of each object in [first, limit) to std::cout with a space character between consecutive elements.

Given: void print(int* first, int* limit);

void print(int* first, int* limit)
{
  while (first != limit) {
    std::cout << *first << ' ';
    ++first;
  }
}

===============================================

When finished, simply test these functions in main()!

1.) // find returns a pointer to the first object in [first, limit) whose value is equal to "value". Return limit if no such object is found

int* find(int* first, int* limit, int value);

2.) // in Returns true if there exists an object in [first, limit) whose value is equal to value and false otherwise. Note: You should be able to implement this by using find.

bool in(int* first, int* limit, int value);

3.) // count returns the number of objects in [first, limit) whose value is equal to "value".

int count(int* first, int* limit, int value);

Answer 1

//####################### PGM START ###########################

#include<iostream>
using namespace std;
//method to print the elements within [first,limit)
void print(int *first,int *limit){
   while(first!=limit){
       cout<<*first<<" ";
       ++first;
   }
}
//method to find the elements within [first,limit)
int* find(int* first,int* limit,int value){
   while(first!=limit){
       if(*first==value){
           return first;
       }
       ++first;
   }
   return limit;
}
//method to check the value is in [first,limit)
//if found return true else return false
bool in(int *first,int* limit,int value){
   int *result=find(first,limit,value);
   if(result==limit)
       return false;
   else
       return true;
}
//method to count the number of times value is within [first,limit)
int count(int* first,int* limit,int value){
   int count=0;
  
   while(first!=limit){
       if(*first==value){
           count++;
       }
       ++first;
   }
   return count;
}
//main method
int main(){
   int a[]={1,2,3,4,5};
   int *first=a+1;
   int *limit=first+3;
   cout<<"Elements with in limit: ";
   print(first,limit);
   cout<<"\n";
   int *result=find(first,limit,2);
   cout<<"Element 2 is in limit: "<<in(first,limit,2)<<"\n";
   cout<<"Element 8 is in limit: "<<in(first,limit,8)<<"\n";
  
   cout<<"Number of times 3 is in limit: "<<count(first,limit,3)<<"\n";
   return 0;
}

//############################## PGM END ########################################

OUTPUT
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