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How to sort a map in C++ STL based on Value, instead of Key

How to sort a map in C++ STL based on Value, instead of Key# Programming - 葵花宝典

i*e2005-11-08 08:11

1 楼

map index_of_card; // ????
I want to sort the index (int) numerically. For example,
index_of_card.begin()->second will print out the samllest value,
index_of_card.end() ->second will print out the largest value, etc.
Thanks!

c*s2005-11-08 08:11

2 楼

为什么不用
map

【在 i******e 的大作中提到】

: map index_of_card; // ????
: I want to sort the index (int) numerically. For example,
: index_of_card.begin()->second will print out the samllest value,
: index_of_card.end() ->second will print out the largest value, etc.
: Thanks!

i*e2005-11-08 08:11

3 楼

I need map. For the time being, I have to use both
map and map.
I have thought map in C++ has the similiar way to be manipulated as
hash in Perl, where we can sort by key or by value.

【在 c****s 的大作中提到】

: 为什么不用
: map

p*f2005-11-08 08:11

4 楼

you can sort c++ map by value if you want, but this would not be the
same sort carried out by the map container. I believe hash sort by
value in perl is the same case, ie. you just pass all the values to a
sort function.

【在 i******e 的大作中提到】

: I need map. For the time being, I have to use both
: map and map.
: I have thought map in C++ has the similiar way to be manipulated as
: hash in Perl, where we can sort by key or by value.

vi2005-11-08 08:11

5 楼

I don't think this is doable without adding signaficant works.
You can't sort by value; and if you do, that's multi-key,
instead of key-value.

【在 i******e 的大作中提到】

i*e2005-11-08 08:11

6 楼

oh, I feel good then. I have been afraid that I implemented sth which was al
ready there.

【在 vi 的大作中提到】

:
: I don't think this is doable without adding signaficant works.
: You can't sort by value; and if you do, that's multi-key,
: instead of key-value.

p*g2005-11-08 08:11

7 楼

just pass a compare function or function object to sort,
your compare function(object) compares
the value instead of the key of your map.

【在 i******e 的大作中提到】