c++11 - C++ Reverse a smaller range in a vector -

what best way following?

i reverse smaller range in vector , haven't found better solution this: extract smaller range newly created vector, reverse , add newly created vector @ former position in original vector.

another way explain want this:

original vector: 1 2 3 4 5 6 7 8 9 10 11.

wanted result:   1 2 3 4 5 6 7 10 9 8 11.

1. copy 10, 9, 8 in order new vector 3 element or copy element 8, 9, 10 new vector reverse it. original vector consists of 9 elements because elements 8, 9, 10 erased in procedure.

2.the new vector 3 elements 10, 9, 8 copied/appended original vector @ position 8 vector or element element @ position 8, 9, 10 respectively.

i sure there better solutions method mentioned above.

you in fact write in-place swap,

• that gets last , first index swap,
• swap these,
• decreases last index , increases first index,
• and repeats until last_index - 1 <= first_index.

now, sounds less copying me, stroustrup himself once said:

i don't understand data structure, i'm pretty sure on real hardware, std::vector kick shit out of it.

i.e. accessing memory linearly faster, cost of copying few numbers on new vector isn't bad, compared having jump , forth, possibly thrashing cpu cache if jumps larger cache line size.

hence, think practical reasons, implementation optimal, unless run out of ram.