最大值和最小值？

Question

I have made a matrix using vector and iterator, how can I find maximum and minimum value from it. It is something like:

vector<int> > matrixes(10);
typedef std::vector<std::vector<int> >::iterator it;

it rows = matrixes.begin();
 if (rows->size() == 10)
++rows;
rows->push_back(res);

}

for(size_t q=0; q < matrixes.size(); ++q)
{
    for(size_t r=0; q < matrixes[q].size(); ++r)
    cout << matrixes[q][r] << " ";
   cout << endl;
}

I want to find maximum and minimum value through it, how is it possible?

Answer 1

在STL中使用std :: max_element和std :: min_element 。

Answer 2

If you have an std::vector, you can do

std::vector<int> my_vector;
//Populate vector
int max = std::max_element( my_vector.begin(), my_vector.end() );

See the reference .

Answer 3

Just add two variables to hold the maximum and minimum value. Update the portion where you display it.

vector<int> > matrixes(10);
typedef std::vector<std::vector<int> >::iterator it;

it rows = matrixes.begin();

int maxVal,minVal;

if ( matrixes.size() > 0 && matrixes[0].size() > 0 )
 maxVal = minVal =  matrixes[0][0];

for(size_t q=0; q < matrixes.size(); ++q)
{
    for(size_t r=0; q < matrixes[q].size(); ++r)
    {        
     cout << matrixes[q][r] << " ";
     cout << endl;
     // update min, max here
     maxVal= maxVal<matrixes[q][r]?matrixes[q][r]:maxVal;
     minVal= minVal>matrixes[q][r]?matrixes[q][r]:minVal;
    } 
}

Answer 4

std::sort( matrixes.begin(), matrixes.end() );

向量中的第一个元素最少，最后一个元素最大。