Spreadsheet Calculator

Calculator.cpp

/***************************
test case format:
3 2
A2
4 5 *
A1
A1 B2 / 2 +
3
39 B1 B2 * /
****************************/
#include <iostream>
#include <string>
#include <stack>
#include <map>
#include <iomanip>
using namespace std;

void initsheet(map<int,string> &str_map, int &width, int &height);
double operaHelper(double first, double second, char opt);
double opera(int order, map<int,string> str_map, map<int,double> &num_map, map<int,bool> &num_flag, int width, int height);

int main() {
  	map<int,string> str_map;
	map<int,double> num_map;
	map<int,bool> num_flag;
	int width,height;

	initsheet(str_map,width,height);
	for(int i=0;i<width*height;i++) {
		if(num_flag[i] == false) {
			num_map[i] = opera(i, str_map, num_map, num_flag, width, height);
		}
	}

	cout << width << " " << height << endl;
	for(int i=0;i<int(num_map.size());i++) {
		cout << fixed;
		cout << setprecision(5) << num_map[i] << endl;
	}
	return 0;
}

//initialize the spreadsheet, first line is width and height, then each cell A(1), A(2), B(1).......
void initsheet(map<int,string> &str_map, int &width, int &height) {
	string wh;
	getline(cin,wh);
	int num=0;
	for(int i=0;i<int(wh.size());i++) {
		if(wh[i]>='0' && wh[i]<='9'){
			num = num*10 + int(wh[i] - '0');
		}
		else if(wh[i]==' ') {
			width = num;
			num = 0;
		}
	}
	height = num;
	for(int i=0;i<width*height;i++) {
		string str_temp;
		getline(cin,str_temp);
		str_map[i] = str_temp;
	}
}

//operator help function, deal with operator '+', '-', '*', '/' between two numbers
double operaHelper(double first, double second, char opt) {
	if(opt == '+'){
		return first + second;
	}
	else if(opt == '-'){
		return first - second;
	}
	else if(opt == '*'){
		return first * second;
	}
	else{
		return first / second;
	}
}

// Key function....
// Scan the string from beginning
// If it's a number, push it to the stack
// If it's a operator, pop two numbers from the stack, after calculation, push the result to the stack
// If it's a symbol of cell, do the recursion
// After finding value of a cell, set its flag true

double opera(int order, map<int,string> str_map, map<int,double> &num_map, map<int,bool> &num_flag, int width, int height) {
	stack<double> num_stk;
	string str = str_map[order];
	double num_temp = 0;
	bool hasNum = false;

	for(int i=0; i<int(str.length());i++) {
		if(str[i]>='A' && str[i]<='Z') {
			int width_temp = 0;
			int order_temp = int(str[i] - 'A')*width;
			for(int j=i+1;j<int(str.length());j++) {
				if(str[j] == ' ') {
					break;
				}
				width_temp = 10*width_temp + int(str[j] - '0');
				i = j;
			}
			order_temp += width_temp - 1;
			if(num_flag[order_temp]) {
				num_stk.push(num_map[order_temp]);
			}
			else {
				num_temp = opera(order_temp, str_map, num_map, num_flag, width, height);
				num_stk.push(num_temp);
				num_temp = 0;
			}
		}
		else if(str[i]>='0' && str[i]<='9') {
			num_temp = 10*num_temp + double(str[i] - '0');
			hasNum = true;
		}
		else if(str[i] == ' ') {
			if(hasNum){
				num_stk.push(num_temp);
				num_temp = 0;
				hasNum = false;
			}
		}
		else if(str[i] == '+' || str[i] == '-' || str[i] == '*' || str[i] == '/') {
			double second = num_stk.top();
			num_stk.pop();
			double first = num_stk.top();
			num_stk.pop();
			double result = operaHelper(first,second,str[i]);
			num_stk.push(result);
		}
	}
	if(hasNum) {
		num_stk.push(num_temp);
		hasNum = false;
	}
	num_map[order] = num_stk.top();
	num_flag[order] = true;
	return num_stk.top();
}