mostafaabdelaal_03's blog

why sorting vector in map does not work ?? Problem D In DIV 3 Round!
By mostafaabdelaal_03, history, 2 months ago, In English 
I get The idea of Problem D Today But I was getting WA and I did not know where is the wrong.. After the contest I discovered that my map donot do sorting to vector of string in it ...

why ???

map<char, vector<string>>mp;
for(auto i:mp){
    sort(i.second.begin(), i.second.end());
}

this is the test that my friend give me after contest:

1

1

D

9H 4H

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2 months ago, # |
  Vote: I like it -6 Vote: I do not like it

you should have done sort(mp[i.first].begin(), mp[i.first].end());

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2 months ago, # |
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Auto comment: topic has been updated by mostafaabdelaal_03 (previous revision, new revision, compare).

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2 months ago, # |
  Vote: I like it +29 Vote: I do not like it

for (auto &i : mp), you just make a copy every time

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    2 months ago, # ^ |
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    Yes it's the reference trick.

    Or you can use iterators: for (auto it=mp.begin();it!=mp.end();it++) sort(it->second.begin(),it->second.end());

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2 months ago, # |
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I think using maps is overcomplicating

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