如何通过函数更改结构中的数据值？

first time posting here, any help would be appreciated. I'm trying to change the value "size" inside my stack called "try", by putting it through my function called Stack_Init. If I print out the value of "stack->size" inside the function, it gives me the correct value for size (being 4). If I were to print first time posting here, any help would be appr