This program illustrates the use of the STL partial_sort_copy() algorithm
(default version) to sort a range of values from a vector of integers of
size 12 into ascending order and copy as many of them as will fit into a
range within a second vector of integers. The contents of the initial
vector are unchanged by this action.
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Here are the initial contents of vector v1:
10 2 6 11 9 3 4 12 8 7 1 5
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Here are the initial contents of vector v2:
100 200 300 400 500
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Now we make the following call:
p = partial_sort_copy(v1.begin(), v1.end(), v2.begin(), v2.begin()+3);
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After that call, here are the contents of v1:
10 2 6 11 9 3 4 12 8 7 1 5
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And here are the contents of v2:
1 2 3 400 500
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The iterator p returned by the algorithm points to the value 400.
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Next we make the following call:
p = partial_sort_copy(v1.begin()+2, v1.end()-2, v2.begin(), v2.end());
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After that call, here are the contents of v1:
10 2 6 11 9 3 4 12 8 7 1 5
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And here are the contents of v2:
3 4 6 7 8
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The iterator p returned by the algorithm points to
the end of the ouput container.
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