C++ Programming Code Examples
C++ > Beginners Lab Assignments Code Examples
Program to Find the Mode in a Data Set
/* Program to Find the Mode in a Data Set
- The mode is the maximum of the count of occurrence of the different data element.
- This algorithm is beneficial for a large dataset with high repetition frequency.
- The worst case time complexity of this algorithm is O(n^2).
- This algorithm inserts the distinct data into linked list in a sorted manner.
- Instead of inserting same data twice it records the occurrence of each data element.
- The maximum occurred among these is the Mode.
- Exit. */
#include <iostream>
using namespace std;
// A structure to represent a node.
struct list
{
int data;
int count;
list *next;
};
// Function to insert data into linked list.
list* insertinlist(list *head, int n)
{
// Creating newnode and temp node.
list *newnode = new list;
list *temp = new list;
// Using newnode as the node to be inserted in the list.
newnode->data = n;
newnode->count = 0;
newnode->next = NULL;
// If head is null then assign new node to head and increase the count.
if(head == NULL)
{
head = newnode;
head->count++;
return head;
}
else
{
temp = head;
// If newnode->data is lesser than head->data, then insert newnode before head and increase the count.
if(newnode->data < head->data)
{
newnode->next = head;
head = newnode;
newnode->count++;
return head;
}
// If newnode->data is equal to the head data then increase count of the head node.
else if(newnode->data == head->data)
{
head->count++;
return head;
}
// Traverse the list till we get value more than or equal to the newnode->data.
while(temp->next != NULL)
{
// If equals to any of the data present in the list then increse the counter and return.
if(newnode->data == (temp->next)->data)
{
(temp->next)->count++;
return head;
}
if(newnode->data < (temp->next)->data)
break;
temp=temp->next;
}
// Insert newnode after temp.
newnode->next = temp->next;
temp->next = newnode;
// Increase the counter.
newnode->count++;
return head;
}
}
int main()
{
int n, i, num, max = 0, c;
// Declaring head of the linked list.
list *head = new list;
head = NULL;
cout<<"\nEnter the number of data element to be sorted: ";
cin>>n;
for(i = 0; i < n; i++)
{
cout<<"Enter element "<<i+1<<": ";
cin>>num;
// Inserting num in the list.
head = insertinlist(head, num);
}
// Printing the sorted data.
cout<<"\nSorted Distinct Data ";
while(head != NULL)
{
if(max < head->count)
{
c = head->data;
max = head->count;
}
cout<<"->"<<head->data<<"("<<head->count<<")";
head = head->next;
}
cout<<"\nThe Mode of given data is "<<c<<" and occurred "<<max<<" times.";
return 0;
}
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Consider a situation, when we have two persons with the same name, jhon, in the same class. Whenever we need to differentiate them definitely we would have to use some additional information along with their name, like either the area, if they live in different area or their mother's or father's name, etc. Same situation can arise in your C++ applications. For example, you might be writing some code that has a function called xyz() and there is another library available which is also having same function xyz(). Now the compiler has no way of knowing which version of xyz() function you are referring to within your code.
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Insert x into the tree; duplicates are ignored. Remove x from the tree. Nothing is done if x is not found. Find the "smallest item" in the tree. Find the "largest item" in the tree. Find
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