Thread: static array is needed but size is not determinable at compile time, what do I do?

Here's the code:

Code:

unsigned int* generatePopulation(const int);


int main(){
    const int POPSIZE = 3;
    unsigned int* population;
    population = generatePopulation(POPSIZE);
    
}


unsigned int* generatePopulation(const int size){
    static int population[size];
    //...fill the array
    return population;
}

Compiler error is:

Code:

error: storage size of ‘population’ isn’t constant

I've searched the error and people recommend that a variable defined with const is still a "variable", however, compiler needs a constant created with #define processor for the size of a static array, however, I can not do this, since I want to get the input from the outside(e.g. using scanf) so a preprocessor command won't help, also the array has to be static or else it will be destroyed after the function call. Is there a way for it? Thanks in advance.

Your only option is to call malloc if your size is user-determined by reading a value using scanf.

Code:

void generatePopulation(unsigned int*,const int);
 
 
int main(){
    const int POPSIZE = 3;
    unsigned int* population = malloc(POPSIZE*sizeof(*population));
    generatePopulation(population,POPSIZE); 
}

void generatePopulation(unsigned int*pop, const int size){
    //...fill the array
}