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I have been trying to solve UVa10226, and my buggy code is given below.

# include "bits/stdc++.h"
# include <cmath>
# include <algorithm>
# include <cstring>
# include <cstdio>

# define vi vector<int>
# define vvi vector<vi>
# define pi pair<int, int>
# define vii vector<pi>
# define rep(i,a,b) for(int i=a; i<b; i++)
# define ll long long int
# define fast ios_base::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);

using namespace std;

int main(int argv, char* argc[]){
    fast
    int n; string s;
    cin>>n;
    getline(cin,s);
    getline(cin,s);
    while(n--){
        map<string,int> mp;
        double total=0;
        while(!cin.eof()){
            getline(cin,s);
            if(s=="") break;
            auto it = mp.find(s);
            if(it==mp.end()) mp.insert({s,1});
            else (it->second)++;
            total++;
        }
        for(auto it=mp.begin(); it!=mp.end(); it++){ cout << it->first << " " << setprecision(4) << fixed << (it->second*100)/total << endl;}
        if(n!=0) cout << endl;
    }
}

Here is the output which the console shows:

 13.7931
 3.4483
 3.4483d
 3.4483
 3.4483alnut
 3.4483
 3.4483ood
 3.4483
 3.4483
 3.4483ry
 3.4483ple
 3.4483
 3.4483
 3.4483
 3.4483er
 3.4483
 6.8966
 3.4483as
 3.4483ple
 3.4483e
 10.3448k
Willow 3.4483
 3.4483Birch

The output is corrected when I add s[s.size()-1]=' ' below the getline() in the inner while loop. I don't understand how getline() works here, and why there is overlap present. I think the last character is '\n' because sending the output to a text file prints out the name and number in different lines.

I would appreciate help regarding how getline() is working here (I don't understand why the two getline() are needed), and why the output in the console is weird (I expected the output in console to be similar to the output obtained in a text file)

(Also, the reason "Willow" appears properly is because it is the last line of the input file)

The output of the textfile:

Ash
 13.7931
Aspen
 3.4483
Basswood
 3.4483
Beech
 3.4483
Black Walnut
 3.4483
Cherry
 3.4483
Cottonwood
 3.4483
Cypress
 3.4483
Gum
 3.4483
Hackberry
 3.4483
Hard Maple
 3.4483
Hickory
 3.4483
Pecan
 3.4483
Poplan
 3.4483
Red Alder
 3.4483
Red Elm
 3.4483
Red Oak
 6.8966
Sassafras
 3.4483
Soft Maple
 3.4483
Sycamore
 3.4483
White Oak
 10.3448
Willow 3.4483
Yellow Birch
 3.4483

Here's the input file which I've been using:

1

Red Alder
Ash
Aspen
Basswood
Ash
Beech
Yellow Birch
Ash
Cherry
Cottonwood
Ash
Cypress
Red Elm
Gum
Hackberry
White Oak
Hickory
Pecan
Hard Maple
White Oak
Soft Maple
Red Oak
Red Oak
White Oak
Poplan
Sassafras
Sycamore
Black Walnut
Willow
Akash Cherukuri
  • 83
  • 5
  • 2
    Please provide sample input to match the desired output. – Yunnosch May 28 '21 at 06:25
  • The input's there in the link provided at the start – Akash Cherukuri May 28 '21 at 06:28
  • Yes I thought so. That is why I asked you to provide it here. – Yunnosch May 28 '21 at 06:30
  • 3
    Please provide a [mre] without relying on external links. Also explain what your code is supposed to do – Alan Birtles May 28 '21 at 06:31
  • 1
    My guess would be that your input file contains Windows line endings but your not on Windows – Alan Birtles May 28 '21 at 06:33
  • 2
    Do you have reasons for using all those (bad) code-golfing habits? – Yunnosch May 28 '21 at 06:33
  • 2
    `#define fast` – please don't do that. You are calling it just once anyway, the macro is just obfuscating without any additional value. – Aconcagua May 28 '21 at 06:33
  • Cannot reproduce on https://www.tutorialspoint.com/compile_cpp_online.php So @AlanBirtles might be right. – Yunnosch May 28 '21 at 06:36
  • 1
    Same for all the other macros. As far as I see you don't even use them (which is good!), so you might as well remove them. – Lukas-T May 28 '21 at 06:36
  • I recommend rather `std::map`. It is not about having extended range (which is at best an additional bonus), but rather for expressing that negative values are meaningless, which is the case if you are just counting trees. – Aconcagua May 28 '21 at 06:36
  • Yes, I think @AlanBirtles is correct; I'm on WSL. I'd appreciate help regarding getline() as well, really don't understand why I need to have it twice at the start. – Akash Cherukuri May 28 '21 at 06:38
  • 1
    What I mean by code-golf habits: https://stackoverflow.com/questions/31816095/why-should-i-not-include-bits-stdc-h https://stackoverflow.com/questions/5431941/why-is-while-feof-file-always-wrong https://stackoverflow.com/questions/1452721/why-is-using-namespace-std-considered-bad-practice – Yunnosch May 28 '21 at 06:39
  • `while(!cin.eof()) { ... }` – this is not how one does input operations. *First* read, *then* test. Apart from, you don't check `fail()` flag that way. Better check the stream state (`if(std::cin)`), but *after* input operation (`if(std::getline(std::cin, s))` – `std::getline` returns the stream it reads from). – Aconcagua May 28 '21 at 06:43
  • Do not count in doubles. That's pretty inefficient. Much better is counting into an integral (e. g. `unsigned int`, `uint32_t`, ...) and cast to double only at the very end, when dividing. – Aconcagua May 28 '21 at 06:54

0 Answers0