Act 7

#pragma warning(disable: 4996)

#include <stdio.h>

int main(void)
{

	double operand1, operand2, answer;
	char operator;
	char charOperandBuffer;


	int scan;


	while (1) {


		scan = 0;


		scan += scanf("%lf", &operand1);


		if (scan == 0) {

			charOperandBuffer = 0;
			scan += scanf("%c", &charOperandBuffer);


			switch (charOperandBuffer) {
			case 'p':

				operand1 = answer;
				break;
			case 'q':

				return(0);
				break;
			}
		}

		scan += scanf(" %c", &operator);
		scan += scanf(" %lf", &operand2);


		if (scan == 3) {


			switch (operator) {
			case '+':

				answer = operand1 + operand2;
				break;

			case '-':

				answer = operand1 - operand2;
				break;

			case '*':

				answer = operand1 * operand2;
				break;

			case '/':



				if (operand2 != 0) {
					answer = operand1 / operand2;
				}
				else {

					printf("invalid output");
					return(0);
				}
				break;

			default:

				printf("invalid input\n");
			}


			printf("ANS = %f\n", answer);

		}
		else {

			printf("invalid input\n");
		}


	}
}