C++ Programming Code Examples
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Sort vector of user-defined values
/* Sort vector of user-defined values */
#include <algorithm>
#include <iostream>
#include <iterator>
#include <string>
#include <vector>
#include <utility>
using namespace std;
typedef pair<int,string> Pair;
inline bool less_than_second( const Pair& b1, const Pair& b2 ){
return b1.second < b2.second;
}
int main( )
{
const char* names[] = { "A","B", "C", "D","E" };
const int values[] = { 18, 20, 26, 30, 41 };
const int num_pairs = sizeof( names ) / sizeof( names[0] );
vector<Pair> pair( num_pairs );
transform( values, values+num_pairs, names,pair.begin(), make_pair<int,string> );
sort( pair.begin(), pair.end() );
vector<Pair>::const_reverse_iterator pair_rend = pair.rend();
for( vector<Pair>::const_reverse_iterator i= pair.rbegin(); i != pair_rend; ++i )
cout << i->first << " - " << i->second;
sort( pair.begin(), pair.end(), less_than_second );
vector<Pair>::const_iterator pair_end = pair.end();
for( vector<Pair>::const_iterator i = pair.begin();
i != pair_end; ++i )
cout << i->second << " - $" << i->first << " values\n";
}
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