This program illustrates the use of the STL partial_sort() algorithm (extended
version) to partially order a vector of integers of size 12 by moving the first
5 values in the given ordering to the beginning of the vector, in the proper
order. The range of values following this value may also be ordered, but the
algorithm does not guarantee this, and you should not expect it. In this case
the order of the elements is determined by one integer preceding another if
and only if it has a smaller digit sum.
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Here are the initial contents of the vector:
92 21 53 84 46 13 41 76 45 61 11 15
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Now we make the following call:
partial_sort(v.begin(), v.begin()+5, v.end(), hasSmallerDigitSum);
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And here are the (partially sorted) contents of the vector,
up to and including its 7th element:
11 21 13 41 15 84 92 76 46 45 53 61
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