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Find and print maximum elements in a vector
/* The following code example is taken from the book
* "The C++ Standard Library - A Tutorial and Reference"
* by Nicolai M. Josuttis, Addison-Wesley, 1999
*
* (C) Copyright Nicolai M. Josuttis 1999.
* Permission to copy, use, modify, sell and distribute this software
* is granted provided this copyright notice appears in all copies.
* This software is provided "as is" without express or implied
* warranty, and with no claim as to its suitability for any purpose.
*/
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
int main()
{
vector<int> coll;
vector<int>::iterator pos;
// insert elements from 1 to 6 in arbitrary order
coll.push_back(2);
coll.push_back(5);
coll.push_back(4);
coll.push_back(1);
coll.push_back(6);
coll.push_back(3);
// find and print maximum elements
pos = max_element (coll.begin(), coll.end());
cout << "max: " << *pos << endl;
}max: 6
Use max_element to get the maximum element in a container
/* The following code example is taken from the book
* "The C++ Standard Library - A Tutorial and Reference"
* by Nicolai M. Josuttis, Addison-Wesley, 1999
*
* (C) Copyright Nicolai M. Josuttis 1999.
* Permission to copy, use, modify, sell and distribute this software
* is granted provided this copyright notice appears in all copies.
* This software is provided "as is" without express or implied
* warranty, and with no claim as to its suitability for any purpose.
*/
#include <cstdlib>
#include <iostream>
#include <vector>
#include <deque>
#include <list>
#include <set>
#include <map>
#include <string>
#include <algorithm>
#include <iterator>
#include <functional>
#include <numeric>
/* PRINT_ELEMENTS()
* - prints optional C-string optcstr followed by
* - all elements of the collection coll
* - separated by spaces
*/
template <class T>
inline void PRINT_ELEMENTS (const T& coll, const char* optcstr="")
{
typename T::const_iterator pos;
std::cout << optcstr;
for (pos=coll.begin(); pos!=coll.end(); ++pos) {
std::cout << *pos << " ";
}
std::cout << std::endl;
}
/* INSERT_ELEMENTS (collection, first, last)
* - fill values from first to last into the collection
* - NOTE: NO half-open range
*/
template <class T>
inline void INSERT_ELEMENTS (T& coll, int first, int last)
{
for (int i=first; i<=last; ++i) {
coll.insert(coll.end(),i);
}
}
using namespace std;
int main()
{
deque<int> coll;
INSERT_ELEMENTS(coll,2,8);
INSERT_ELEMENTS(coll,-3,5);
PRINT_ELEMENTS(coll);
//maximum
cout << "maximum: "
<< *max_element(coll.begin(),coll.end())
<< endl;
}2 3 4 5 6 7 8 -3 -2 -1 0 1 2 3 4 5
maximum: 8
Use max_element to get the maximum value
#include <algorithm>
#include <functional>
#include <iomanip>
#include <iostream>
#include <vector>
using namespace std;
int main(){
const float a[] = { 13.4, 27.6, 15.5, 44.3, 51.2, 30.2, 18.0 };
vector<float> data( a,a + sizeof( a ) / sizeof( a[0] ) );
float data_min = *min_element( data.begin(), data.end() );
float data_max = *max_element( data.begin(), data.end() );
cout << data_max;
}Use max_element with criteria function
/* The following code example is taken from the book
* "The C++ Standard Library - A Tutorial and Reference"
* by Nicolai M. Josuttis, Addison-Wesley, 1999
*
* (C) Copyright Nicolai M. Josuttis 1999.
* Permission to copy, use, modify, sell and distribute this software
* is granted provided this copyright notice appears in all copies.
* This software is provided "as is" without express or implied
* warranty, and with no claim as to its suitability for any purpose.
*/
#include <cstdlib>
#include <iostream>
#include <vector>
#include <deque>
#include <list>
#include <set>
#include <map>
#include <string>
#include <algorithm>
#include <iterator>
#include <functional>
#include <numeric>
/* PRINT_ELEMENTS()
* - prints optional C-string optcstr followed by
* - all elements of the collection coll
* - separated by spaces
*/
template <class T>
inline void PRINT_ELEMENTS (const T& coll, const char* optcstr="")
{
typename T::const_iterator pos;
std::cout << optcstr;
for (pos=coll.begin(); pos!=coll.end(); ++pos) {
std::cout << *pos << " ";
}
std::cout << std::endl;
}
/* INSERT_ELEMENTS (collection, first, last)
* - fill values from first to last into the collection
* - NOTE: NO half-open range
*/
template <class T>
inline void INSERT_ELEMENTS (T& coll, int first, int last)
{
for (int i=first; i<=last; ++i) {
coll.insert(coll.end(),i);
}
}
using namespace std;
bool absLess (int elem1, int elem2)
{
return abs(elem1) < abs(elem2);
}
int main()
{
deque<int> coll;
INSERT_ELEMENTS(coll,2,8);
INSERT_ELEMENTS(coll,-3,5);
PRINT_ELEMENTS(coll);
cout << "maximum of absolute values: "
<< *max_element(coll.begin(),coll.end(),
absLess)
<< endl;
}2 3 4 5 6 7 8 -3 -2 -1 0 1 2 3 4 5
maximum of absolute values: 8
