usaa18cv4/calculator.c

#include "calculator.h"
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <stdio.h>
#include <stdbool.h>

struct stack* create_stack() {
    
	struct stack* s = calloc(1,sizeof(struct stack));

	s-> array = (float*) calloc(STACK_SIZE,sizeof(float));
	s-> size = 0;

    return s;
}

void delete_stack(struct stack* stack) {

	free(stack->array);
    free(stack);
}
/**
 * Ulozenie hodnoty do zasobnika.
 * Funkcia upravi velkost zasobnika a vlozi novu hodnotu.
 *
 * Zabezpecte pomocou funkcie assert aby program spadok ak v zasobniku nie je dost miesta.
 *
 * @arg zasobnik do ktoreho sa ma hodnota ulozit.
 * @arg hodnota, kotra sa ma ulozit.
 */
void  push_stack_value(struct stack* stack,float value) {

	if (stack->size >= STACK_SIZE)
	{	//Dynamic allocation
		
		float* new_array = (float*) calloc(stack->size+1,sizeof(float));

		memcpy(new_array,stack->array,stack->size*sizeof(float));

		new_array[stack->size++] = value;

		stack -> array = new_array;
		
	}

	else
		stack-> array[stack->size++] = value;		
}

/**
 * Vybratie hodnty zo zasobnika.  Funkcia zmensi velkost zasobnika.
 * Zabezpecte, aby program spadol ka v asobniku nie je doststok hodnot. (velkost nesmie byt mensia ko nula)
 *
 * @arg zasobnik
 *
 * @retrun hodnota na vrchu zasobnika.
 */
float pop_stack_value(struct stack* stack) {

	assert(stack->size>0);
	
	float val = stack->array[stack->size-1];
	stack-> array[stack->size--]=0;
	
    return val;
}


/**
 * Vypis obsahu zasobnika.
 */
void print_stack(struct stack* stack) {
int i;
for ( i = 0; i < stack-> size; i++)

	printf("%.2f ",stack->array[i]);

	printf("\n");

}

static bool is_float(char* str) {

return
	(str[0]=='+'||str[0]=='-'||str[0]=='*'||str[0]=='/') 
	? false : true;
}

/**
 * Cela polska kalkulacka.
 */
void polish_calculator() {

	char* input= calloc(100,sizeof(char));
	struct stack* stack = create_stack();


	while(1)
	{

		scanf("%s",input);

	if (is_float(input))
	{
		push_stack_value(stack,atof(input));
		print_stack(stack);
	}

	else 
	{

		if (stack->size<2) 	
		{
			printf("Nedostatok hodnot v stacku\n");
			break;
		}
		

		switch(input[0])
		{

			case '+':
				push_stack_value(stack,pop_stack_value(stack)
					+ pop_stack_value(stack));
				break;

			case '-':
				push_stack_value(stack,pop_stack_value(stack)
					- pop_stack_value(stack));
				break;

			case '*':
				push_stack_value(stack,pop_stack_value(stack)
					* pop_stack_value(stack));
				break;

			case '/':
				push_stack_value(stack,pop_stack_value(stack)
					/ pop_stack_value(stack));
				break;

			default: printf("Nespravny operand\n");

		}

		print_stack(stack);

	}

	}


	free(input);
	delete_stack(stack);

}