strange error

[3vX4LyTq]

Not sure how I messed up, but I get an error that simply states "exited with non-zero status"

sigh

What did I do wrong?

PS If it helps, I use repl.it to compile and write my code

    srand(time(NULL));
    vector<int> listo;
    for(int i = 0; i<20; i++){
      listo[i] = rand() % 100 + 1;//Fills vector with 20 random integers
      std::cout << listo[i] << " ";//Prints the vector
     }

[gunnerfunner]

You haven't allocated memory for the vector yet:

#include <iostream>
#include <vector>
#include <cstdlib>
#include <chrono>

int main()
{
    srand(std::time(NULL));
    std::vector<int> listo;
    for(int i = 0; i<20; i++){
      listo.push_back(rand() % 100 + 1);//Fills vector with 20 random integers
      std::cout << listo[i] << " ";//Prints the vector
     }
}

edit: another alternative is to allocate vector memory upon declaration:

std::vector<int> listo(20);
//then
listo[i] = rand()%100+1;

ps: rand() is not a good way to generate random #s, search this forum over the past week or so for better alternatives

[3vX4LyTq]

Haha LOL.

Now I realise I used a vector rather than an array.

[Hengry]

You didn't declare the size of the vector.
You can make it

vector<int>listo(20);
for(int i = 0; i<20; i++){
      listo[i] = rand() % 100 + 1;//Fills vector with 20 random integers
      std::cout << listo[i] << " ";//Prints the vector
}

But I would assume you wanted to use

listo.push_back(rand() % 100 + 1);