How do I ask the user to type the vector size?

Question

I’m just using vectors with a defined number using the define or even direct on the variable. How I put the amount of vectors the user chooses?.

example:

    #define NUMERO x

    int main()
    {
    int valor[NUMERO];

I want this x to be a number that the user can type (choose) at the beginning of the program.

Answer 1

int main(){
    int x=10;
    int valor[x];
}

It’s the same thing as doing

int main(){
    int valor[10];
}

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Or using define

// #define x ValorPredefinido 
#define x 10 /** EXEMPLO, caso saiba que será esse valor **/ 

int main(){
    int valor[x];
}

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From the codes below we do not know how much will be needed at the outset.

int main(){
    int x;
    printf("Qual o tamanho do vetor?"); 
    scanf("%d", &x); /** caso seja um valor que o usuário terá de colocar**/
    int valor[x];
}

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Another option is to use dynamic memory.

int main(){
  int *valor;
}

Go allocating memory as you need more space.

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• What you can’t do is int valor[x] without having a value, in the examples up when it comes to that line x will have a value