This program illustrates the use of the STL partial_sort() algorithm (default
version) to partially sort a vector of integers of size 12 by getting its
5 smallest values into ascending order at the beginning of the vector. The
following range of values may also be sorted (by chance), but the algorithm
does not guarantee this, and you should not expect it
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Here are the initial contents of the vector:
10 2 6 11 9 3 4 12 8 7 1 5
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Now we make the following call:
partial_sort(v.begin(), v.begin()+5, v.end());
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And here are the (partially sorted) contents of the vector,
up to and including its 5th element:
1 2 3 4 5 11 10 12 9 8 7 6
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