C++ Programming Code Examples
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The generic stable_sort algorithms with predicate
/* The generic stable_sort algorithms with predicate */
#include <vector>
#include <algorithm>
#include <iostream>
#include <iterator>
using namespace std;
class comp_last {
public:
bool operator()(int x, int y) const
// Compare x and y based on their last base-10 digits:
{
return x 10;
}
};
int main()
{
const int N = 20;
vector<int> vector0;
for (int i = 0; i < N; ++i)
vector0.push_back(i);
vector<int> vector1 = vector0;
ostream_iterator<int> out(cout, " ");
cout << "Before sorting:\n";
copy(vector1.begin(), vector1.end(), out);
cout << endl;
sort(vector1.begin(), vector1.end(), comp_last());
cout << "After sorting by last digits with sort:\n";
copy(vector1.begin(), vector1.end(), out);
cout << endl << endl;
vector1 = vector0;
cout << "Before sorting:\n";
copy(vector1.begin(), vector1.end(), out);
cout << endl;
stable_sort(vector1.begin(), vector1.end(), comp_last());
cout << "After sorting by last digits with stable_sort:\n";
copy(vector1.begin(), vector1.end(), out);
cout << endl << endl;
return 0;
}
/*
Before sorting:
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
After sorting by last digits with sort:
10 0 11 1 12 2 13 3 4 14 5 15 6 16 7 17 8 18 9 19
Before sorting:
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
After sorting by last digits with stable_sort:
0 10 1 11 2 12 3 13 4 14 5 15 6 16 7 17 8 18 9 19
*/
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Sort elements in range. Sorts the elements in the range [first,last) into ascending order. The elements are compared using operator< for the first version, and comp for the second. Equivalent elements are not guaranteed to keep their original relative order (see stable_sort). C++ Algorithm sort() function is used to sort the elements in the range [first, last) into ascending order. The elements are compared using operator < for the first version, and comp for the second version. std::sort() is a built-in function in C++'s Standard Template Library. The function takes in a beginning iterator, an ending iterator, and (by default) sorts the iterable in ascending order. The function can also be used for custom sorting by passing in a comparator function that returns a boolean.
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