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POPointers to a class within void function
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copied!<p>I am learning how classes/inheritances/pointers work in C++ and coding the following. </p> <p>I have a class <strong>unit</strong> declared as such:</p> <pre><code>class unit{ public: int locationX,locationY; //genotype (does not change) float agility, build,size,stamina, aggression; //phenotype (changes based on genotype and stimuli) float speed, strength, hunger; }; </code></pre> <p>When I create a new instance to pass into a void function (below, respectively), the memory is not allocated yet.</p> <p><strong>Instance</strong></p> <pre><code>unit **units = 0; </code></pre> <p><strong>Void Function Prototype</strong></p> <pre><code>void initialize(grid *grids, unit **units /*, plant **plants, predator **predators */); </code></pre> <p>The memory is allocated within the void function using some parameters:</p> <pre><code>void initialize(grid *grids, unit **units,plant **plants,predator **predators) { units = new unit*[int(((grids->gridHeight)*(grids->gridWidth)*(grids->gridDivision))/20)]; for(register int i = 0; i<int(((grids->gridHeight)*(grids->gridWidth)*(grids->gridDivision))/20); i++) { units[i] = new unit; units[i]->hunger = 5; units[i]->locationX = (rand()%((grids->gridWidth)-0)); units[i]->locationY = (rand()%((grids->gridHeight)-0)); //etc, etc } } </code></pre> <p>However, once I exit the void function, the data I just stored gets deleted. Is there something wrong with the pointer declarations and passing into the function (which is as follows)?</p> <pre><code>initialize(&environment, units, plants, predators); </code></pre> <p><strong>NOTE</strong>: I only have problems with the <em>units</em> variable declared under <strong>unit</strong> class. The <em>environment</em> variable is fine. The other two (<em>plants</em> and <em>predators</em>) are similar to <em>units</em>, so if this is fixed, I can fix the others.</p> <p><strong>Second Note</strong>: The main function is as follows (relevant parts):</p> <pre><code>int main() { unit **units = 0; //<--- Important one plant **plants = 0; predator **predators = 0; grid environment(250,250,5); //Constructor for environment (don't mind this) initialize(&environment, units, plants, predators); //<-- Void function running = true; return 0; } </code></pre> <p>Thank you for any help/links/explanations you can provide.</p>

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