#why cant i move to the left in my code?

26 messages · Page 1 of 1 (latest)

undone musk
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I made a simple code where you can move the letter "o" with w a s d through 2 vectors, and i cant move it to the left more than 1 time,can anybody help me fix this issue?

📎 vector_test.txt
molten oasisBOT
#

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Remember to ask specific questions, provide necessary details, and reduce your question to its simplest form. For tips on how to ask a good question use !howto ask.

dim tundra
#

your for loop goes from smallest to greatest and you're moving the o to the left when you press a

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it will work once it gets to the sixth index but after that I think it won't check that position

#

Btw, don't use

#include <bits/stdc++.h>

use this instead

#include <iostream>
undone musk
#

I use #include <bits/stdc++.h> brcause its easyer to remember compared to everything else

dim tundra
#

Alright, I found the actual problem lol

#

your i is not initalizied

undone musk
#

I replied to the wrong message

dim tundra
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!f

molten oasisBOT
#

I kinda gave it away but can you fix the code in this part


if (ch == 'a') {
  system("clear");
  for (int i = 0; i < 11; i++) {
    if (v[i] == 'o') {
      v[position] = ' ';
      position--;
      v[position] = 'o';
      break;
    } else if (v2[i] == 'o') {
      v2[position] = ' ';
      position--;
      v2[position] = 'o';
      break;
    }
  }
} else if (ch == 'd') {
  system("clear");
  for (int i = 0; i < 11; i++) {
    if (v[i] == 'o') {
      v[position] = ' ';
      position++;
      v[position] = 'o';
      break;
    } else if (v2[i] == 'o') {
      v2[position] = ' ';
      position++;
      v2[position] = 'o';
      break;
    }
  }
nou
undone musk
#

What did you change in the code?

dim tundra
#

Look at how the variable i in the for loops

# 
int i;
std::cout << i; 
// this will be undefined behavior because i is not initalizied or assigned a value.
undone musk
#

So i=0 was the thing that made my code work?

dim tundra
#

Just using

int i;
``` was what was wrong
undone musk
#

Int i doesnt mean that i is 0?

#

so just because "=0" was missing my code didnt work

dim tundra
#

Things will only be automatically initialized in C++ if

  1. it's a class/struct instance in which the default constructor initializes all primitive types; like MyClass instance;

  2. you use array initializer syntax, e.g. int a[10] = {} (all zeroed) or int a[10] = {1,2}; (all zeroed except the first two items: a[0] == 1 and a[1] == 2)

  3. same applies to non-aggregate classes/structs, e.g. MyClass instance = {};

  4. it's a global/extern variable

  5. the variable is defined static (no matter if inside a function or in global/namespace scope)

Got all this from Stackoverflow

undone musk
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oh ok

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im kind of new to cpp and i didnt know this

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tysm for helping me

dim tundra
#

The one you used was automatic storage duration, so you always have to initialize it

dim tundra
undone musk
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!solved