question regarding strings as inputs and parsing

[urban quiver]

Hey so I just finished a leetcode type question (https://dmoj.ca/problem/lkp18c2p1 if you want to take a look). The question regarded taking 2 lines of input from user, ex:

3 4
3 2 5

In my answer, since I ever only really used the getline function to put input strings into variables, then stoi(variable) to make it an integer, I was just wondering if there was a different way of doing this (with less code). In the book that i am going through, the author writes his answer in C, and uses the scanf function, but ever since starting c++ ive never seen that

[fiery token]

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[urban quiver]

#include <iostream>
#include <string>
#include <vector>
//input 3  4 
//      3  2  5

//output
//      2
//      3
//      3
//      4

int find_shortest(int lines[], int n)
{
    int shortest = 0;
    for (int i = 1; i < n; i++)
    {
        if (lines[i] < lines[shortest])
            shortest = i;
    }
    return shortest; //returns smallest index with smallest people in line (smallest integer)
}

void solve(int lines[], int n, int m)
{
    int shortest;
    for (int i = 0; i < m; i++)
    {
        shortest = find_shortest(lines, n);
        std::cout << lines[shortest] << "\n";
        lines[shortest]++;
    }
}



int main()
{
    // int test_lines[] = {3, 2, 5};
    // solve(test_lines, 3, 4);
    std::string sn, sm;
    int n, m;
    getline(std::cin, sn, ' ');
    getline(std::cin, sm);
    n = std::stoi(sn);
    m = std::stoi(sm);
    int lines[100];
    std::string scurrent;
    for (int i = 0; i < n; i++)
    {
        if (i != n - 1)
        {
            getline(std::cin, scurrent, ' ');
            lines[i] = stoi(scurrent);
        }
        else{
            getline(std::cin, scurrent);
            lines[i] = stoi(scurrent);
        }
    }

    solve(lines, n, m);
    return 0;
}

my answer if anyone is interested^

[wraith quartz]

Why not use std::cin for string sn, since the delimiter is a space anyways

If you use cin, you'll have to use cin.ignore(numeric_limits<streamsize>::max(), '\n') but that should be fine

[rocky sparrow]

same with scurrent

inside if(i != n-1)

why u even need if statment her?

just put else outside the loop

without else of course

[wraith quartz]

What is this link btw?

The description lol

[wraith quartz]

I don't think that would make a big difference. It might be even cleaner the way it is right now

[rocky sparrow]

first each iteration of the loop will call if

second it will still have less code...

[wraith quartz]

You mean like this or something different?

 for (int i = 0; i < n; i++)
    {
       getline(std::cin, scurrent, ' ');
       lines[i] = stoi(scurrent);
    }
getline(std::cin, scurrent);
lines[n-1] = stoi(scurrent);
    }

[rocky sparrow]

for(int i = 0; i < n-1; i++)
{
  std::cin >> scurrent;
  lines[i] = stoi(scurrent);
}
getline(std::cin, scurrent);
lines[n-1] = stoi(scurrent);

[rocky sparrow]

ye

and n-1 in check

i will try make this code better

[urban quiver]

its from some competitive programming event question idk the description is pretty funny lmao

[urban quiver]

so i can techinally replace every getline with just std::cin >> scurrent(or whatever var im using there)

[wraith quartz]

If you want to make the code shorter, it's a good way of doing it but the previous code while being a little longer is more clear, so I would personally prefer that

[rocky sparrow]

btw @urban quiver do u allow to use std::array?

because most code look like c

i mean c style

[urban quiver]

idk what that is

like just initializing array

like int array[];

[rocky sparrow]

std::array<type, size>

[urban quiver]

ohhh idk ive never used that you probably can

[rocky sparrow]

use it

it just better

[urban quiver]

isnt vector just better in all cases tho

std::vector<type>

[rocky sparrow]

no

if u need array

[urban quiver]

ohh well

if i alr know the array length

yea i understand

[rocky sparrow]

u can get size

[urban quiver]

oh like .size()

[rocky sparrow]

and iterators work too

[urban quiver]

yea i seen that i couldnt do .size() or .length() for regularly initialized array

[rocky sparrow]

which u can use with raw array but

[urban quiver]

do i have to #include <array>

[rocky sparrow]

yup

[urban quiver]

ahh ok bet

so is that what people mean when they say c-style array

its the std::array

[rocky sparrow]

yup

i mean it just raw array

[urban quiver]

and regular array that is like int array[];

thats just stupid array

[wraith quartz]

That's a C-style array. std::array can be passed to or returned from functions by value, its interface also makes it more convenient to find the size

[urban quiver]

ok i understand i think

[rocky sparrow]

and now u can use std::min_element for find shortest

[wraith quartz]

;compile

#include <iostream>
#include <string>
#include <vector>
#include <array>

void add(std::array<int, 100> &b){
    int size = b.size();
    std::cout << size;
}

int main()
{
   std::array<int, 100> a = {1,2,3,4,5};
   add (a);
}

[stoic spade]

Program Output

100

nou2917 | 41ms | c++ | x86-64 gcc 14.2 | godbolt.org

[wraith quartz]

If you use std::array, you don't have to pass in int n which represents the size to solve and find_shortest functions

[rocky sparrow]

template<size_t s = 0>
int find_shortest(const std::array<int, s>& lines)
{
    return *std::min_element(lines.cbegin(), lines.cend());
}

or just u can remove fully this function

void solve(std::array<int, s>& lines, int m)
{
    int shortest;
    for (int i = 0; i < m; i++)
    {
    shortest = *std::min_element(lines.cbegin(), lines.cend());
        std::cout << lines[shortest]++ << "\n";
    }
}

[rocky sparrow]

@urban quiver btw better to use iftream if u have test values already

because then u not need input anything

u just run and check result