DZ9_2

#include <stdio.h>
#include <conio.h>

class Repository {
	private: 
		int Arr[1000];
		int count;
	public:
	   	Repository() {
			count=0;
		}
		int isEmpty() {
			return !count;
		}
		void set(int x) {
			if (count < 1000) {
			    Arr[count++]=x;
			}
		}
		void setFirst(int x) {
			if (count < 1000) {
				for (int i=count; i > 0; i--) Arr[i]=Arr[i-1];
			    Arr[0]=x;
			    count++;
			}
		}
		int get() {
			int temp;
			if (count > 0) {
				temp=Arr[0];
				for (int i=1; i < count; i++) Arr[i-1]=Arr[i];
				count--;
				return temp;
			}
			return -1;
		}
		int getCount() { 
			return count;
		}
};

double calc(char* str) {
	int res =0;
	Repository rNum;
	int temp=0;
	int isPrewNum = 0;
	
	for (int i=0; str[i] != '\0'; i++) {
		
		for (;str[i] >= 48 && str[i] <= 57; i++) {
			temp*=10;
			temp += str[i] - 48;
			isPrewNum = 1;
		}
		if (isPrewNum) {
			rNum.set(temp);
			temp = 0;
			isPrewNum = 0;
		}
		
		switch (str[i]) {
			case '+':
				if (rNum.getCount() == 2) {
					res = rNum.get() + rNum.get();
					rNum.setFirst(res);
				}
				break;
			case '-':
				if (rNum.getCount() == 2) {
					res = rNum.get() - rNum.get();
					rNum.setFirst(res);
				}
				break;
			case '*':
				if (rNum.getCount() == 2) {
					res = rNum.get() * rNum.get();
					rNum.setFirst(res);
				}
				break;
			case '/': 
				if (rNum.getCount() == 2) {
					res = rNum.get() / rNum.get();
					rNum.setFirst(res);
				}
				break;
		}
		
		
	}
	
	return res;
}

int main(){
	char* str = "5 6 + 3 * 22 -";
	int res = calc(str);
	printf("res = %i", res);
	getch();
	return 0;
}