modevalue of an array

[Larry]

Hi,

I need to calculate the modevalue (number that coocurs the most) of an
array like this:

short values[5] = {1,1,2,3,4};

can it actually be done?

thanks

 

[John H.]

I need to calculate the mode of an array
can it actually be done?

Yes it can be done.
If you post some of your efforts at doing this so far, we might be
able to help you more.

 

[Larry]

Yes it can be done.
If you post some of your efforts at doing this so far, we might be
able to help you more.

#include <iostream>
#include <map>
using namespace std;

#define length(x) (sizeof (x) / sizeof *(x))

int main()
{
int a[] = {1,2,9,5,6,4,8,1,2,1,7,9,8,9,9,9,9,9};

map<int,int> freq;

for ( size_t i = 0; i < length ( a ); i++ )
{
++freq[a];
}

map<int,int>::const_iterator it = freq.begin();

while ( it != freq.end() )
{
cout<< it->first <<": "<< it->second <<endl;
++it;
}

return 0;
}

 

[Rolf Magnus]

Yes it can be done.
If you post some of your efforts at doing this so far, we might be
able to help you more.

#include <iostream>
#include <map>
using namespace std;

#define length(x) (sizeof (x) / sizeof *(x))

int main()
{
int a[] = {1,2,9,5,6,4,8,1,2,1,7,9,8,9,9,9,9,9};

map<int,int> freq;

for ( size_t i = 0; i < length ( a ); i++ )
{
++freq[a];
}

map<int,int>::const_iterator it = freq.begin();

while ( it != freq.end() )
{
cout<< it->first <<": "<< it->second <<endl;
++it;
}

return 0;
}

That's a good start. Now all you need to in your second loop is remember the
pair that had the largest value for it->second you have encountered so far
(*it is of type std:air<int, int>). After the loop, the first member of
that pair is what you were searching for.