vector sort for high scores

[toefraz]

Hi, guys. I'm writing a little game, and I want to include a high scores list.
I've got everything coded except for the sorting part. I want to use the std::sort() function, but I'm not quite sure how I could get it to work with the data in my vector.

Here is a sample high score file in which each line is inputted into a vector element. I want to sort by the score:

2345     toefraz     day time year
1009     toe           day time year
8794     toejamb    day time year
...

Any ideas?

[toefraz]

I sort of got it working by using

sort(v.begin(), v.end(), greater<string>());

but it is sorting the scores like this:

975       toefraz   Sun Jan 13 03:33:01 2008
550       toefraz   Sun Jan 13 04:07:07 2008
440       toefraz   Sun Jan 13 04:19:52 2008
330       toefraz   Sun Jan 13 04:26:21 2008
323       toefraz   Sun Jan 13 03:33:01 2008
25        toefraz   Sun Jan 13 03:34:24 2008
220       toefraz   Sun Jan 13 04:36:15 2008
220       toefraz   Sun Jan 13 04:06:01 2008
1230      toefraz   Sun Jan 13 03:33:01 2008
1090      toefraz   Sun Jan 13 03:33:01 2008

whereas I need them to be sorted by numerical value. I'm pretty sure it's because i'm using strings and that's how they sort. How would I go about sorting them properly

[Savage]

You will need to create a simple struct,containi ng hi-score,name,and date(and other information you desire).After that you would create a vector of this structs and sort them by hi-score member.Offcours e you would need to write your own compare function and pass it as the third argument.

[toefraz]

Oh ok. We haven't gotten to structs yet in class. I'll research them. Thanks for you help.

[intOwnsVoid]

The STL (Standard Template Library) defines a group of algorithms that allow you to manipulate elements in containers through iterators.

#include <iostream>
#include <vector>
#include <algorithm> // Added to be able to use the STL algorithms
 
using namespace std;
 
int main ()
{
    // This is how you define an iterator in this case i made it constant
    vector<int>::const_iterator iter; 
 
    cout << "Creating a list of scores.\n";
    // declaring a vector named scores that contain integer object elements
    vector<int> scores; 
    scores.push_back (4500);
    scores.push_back (3500);
    scores.push_back (234);
 
    cout << "Printint the list of scores.\n";
    for (iter = scores.begin(); iter != scores.end(); ++iter)
        cout << *iter << endl;
 
    cout << "\n\nSorting scores.\n";
    sort (scores.begin(), scores.end());
    for (iter = scores.begin(); iter != scores.end(); ++iter)
        cout << *iter << endl;
 
    system("PAUSE");
    return (0);
}
 

[amalestale]

You will need to create a simple struct,containi ng hi-score,name,and date(and other information you desire).After that you would create a vector of this structs and sort them by hi-score member.Offcours e you would need to write your own compare function and pass it as the third argument.

Hi, i think i tried to do what you mentioned but i am getting errors:

// sort algorithm example
#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;

bool myfunction (int i,int j) { return (i<j); }

class tryClass
{
public:
int a, b;
};
int main ()
{
tryClass *temp_Obj;

vector<tryClass > myvector;
vector<tryClass >::iterator it;

for(int i=1; i<= 8; i++)
{
temp_Obj = new(tryClass);
(*temp_Obj).a = 100 - i;
(*temp_Obj).b = i+10;
myvector.push_b ack(*temp_Obj);
}

// using function as comp
//sort (myvector.begin (), myvector.end(), myfunction);

// print out content:
cout << "myvector contains:" << endl;
for (it=myvector.be gin(); it!=myvector.en d(); ++it)
cout << " (" << (*it).a << ", " << (*it).b << ")" << endl;

cout << endl;
return 0;
}

Any suggestions?

[amalestale]

sorry ... please ignore comment infront at the beginning of the sort line

[amalestale]

phew, ok...i think i got it...(was making a lot of stupid mistakes!!)
below is what i think works....

// sort algorithm example
#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;

class tryClass
{
public:
int a, b;
};

bool myfunction (tryClass& left, tryClass& right) { return ( left.a < right.a ); }

int main ()
{
tryClass *temp_Obj;
vector<tryClass > myvector;
vector<tryClass >::iterator it;

for(int i=1; i<= 8; i++)
{
temp_Obj = new(tryClass);
(*temp_Obj).a = 100 - i;
(*temp_Obj).b = i+10;
myvector.push_b ack(*temp_Obj);
}

// using function as comp
sort (myvector.begin (), myvector.end(), myfunction);

// print out content:
cout << "myvector contains:" << endl;
for (it=myvector.be gin(); it!=myvector.en d(); ++it)
cout << " (" << (*it).a << ", " << (*it).b << ")" << endl;
cout << endl;

return 0;
}

[Laharl]

That looks like it should work, though I have one comment: Every time you use new, get in the habit of using delete (or delete[] for arrays) to de-allocate the memory.