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Hello there, Semi-advanced calculator with multiplication/division/remainder priority

Macaque (1)
hey there - I am a C++ beginner, and I'm making a semi-advanced calculator which will calculate such things like 2+9*10 and will get 92, not 110.

I need quick help from pros, and I can't compile the C++ code due to libraries such as #include <array> arent supported by g++ or something.
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#include <iostream>
#include <iomanip>
#include <cmath>
#include <array>
/* run this program using the console pauser or add your own getch, system("pause") or input loop */
using namespace std;
int main() {
	//Nustatymas

	double atmintis;

	double a[100] = {};
	double b[100] = {};
	int kurSudetis[200] = {};
	int kurAtimtis[200] = {};
	int kurApvertimas[200] = {};
	double M;
	int ind2 = 0;
	int ind3 = 0;
	int ind4 = 0;
	int ind;
	double atsakymas;
	char zenklas[300] = {};
	bool lygu = false;
	//Ivedamw reiskini
	cout << "iveskite reiskini. /n" << "Naudokite +, -, *, /, %, a(apvertimas - 1/x) aritmetiniams reiskiniams /n"<< "Atminciai naudokite P(M+), M(M-), S(MS), R(MR), C(MC) /n";
	cout << "apvertimas apvers TIK antraji skaiciu. Bet geriau naudoti dalini tada /, tada dalikli /n";
	while(lygu = false){
		//vedame iki =
		for(int i = 0; i < 101; i++){
			cin >> a[i] >> zenklas[i] >> b[i];
			if(zenklas[i] == '='){
				cout << "pradedame skaiciuoti /n";
				lygu = true;
			}
		}
		
	}
	//Nustateme, kada vartotojas iveda lygybes zenkla
	//O dabar skaiciuojame
	//Dauginame, daliname(for)
	for(int n = 0; n < zenklas.size(); n++){
		//skaiciuojame tol, kol gauname kazka		
		//is pradziu dauginame, daliname, %, 1/x
		switch(zenklas[n]){
			case "*":
				{
					ind = n%2;
					if(ind = 1){
						//Nustatome, ar indeksas yra lyginis, ar nelyginis
						//Numetame atsakyma i B
						b[n] = a[n]*b[n];
					} else {
						//Numetame atsakyma i A
						a[n] = a[n]*b[n];
					}
					n--;
					break;
				}
			case "/": //tas pats, kas virsui, tik sudalijama
				{
					ind = n%2;
					if(ind = 1){
						//Nustatome, ar indeksas yra lyginis, ar nelyginis
						//Numetame atsakyma i B
						b[n] = a[n]/b[n];
					} else {
						//Numetame atsakyma i A
						a[n] = a[n]*b[n];
					}
					n--;
					break;
				}
			case "%": //modulis 
			{
					ind = n%2;
					if(ind = 1){
						//Nustatome, ar indeksas yra lyginis, ar nelyginis
						//Numetame atsakyma i B
						b[n] = fmod(a[n],b[n]);
					} else {
						//Numetame atsakyma i A
						a[n] = fmod(a[n],b[n]);
					}
					n--;
					break;
				}
			case "+":{ //nu va dabar tai rikiuojam veiksmus
			    
				kurSudetis[ind2] = n;
				ind2++;
				break;
			}
			case "-":{
				kurSudetis[ind3] = n;
				ind3++;
				break;
			}
			case "a":{
				kurApvertimas[ind4] = n;
				ind4++;
				break;
			}
			
		}
			}
	

//sitas kodas sudaugina ir dalina, ir meta liekana(fmod()), ir nurodo tolesnei programos daliai, kur reikia sudeti, atimti, ir apversti;

//o dabar sudedame ir atimame: - si progr
for(int w = 0; w < ind2[].size(); w++){ //isimtinai sudetis
	ind = ind2[w] % 2;
	if(ind =1){
		b[kurSudetis[ind2]] = a[kurSudetis[ind2]]+b[kurSudetis[ind2]];
	} else {
		a[kurSudetis[ind2]] = a[kurSudetis[ind2]]+b[kurSudetis[ind2]];
	}
	
}

for(int w = 0; w < ind3[].size(); w++){ //isimtinai sudetis
	ind = ind3[w] % 2;
	if(ind =1){
		b[kurAtimtis[ind3]] = a[kurAtimtis[ind3]]-b[kurAtimtis[ind3]];
	} else {
		a[kurAtimtis[ind3]] = a[kurAtimtis[ind3]]-b[kurAtimtis[ind3]];
	}
	
}

for(int w = 0; w < ind2[].size(); w++){ //isimtinai sudetis

b[kurApvertimas[ind4]] = 1/b[kurSudetis[ind2]];

}

cout << "jusu skaicius yra" << a+b;

}


explanation - a is primary input, but also output component as it has even number
b is secondary input, also component, has odd number

The main task is to make sure the calculator prioritizes multiplication and division, also modulus. Also I would like you to add M+, M-, MC, MR, MS memory operations.

Cheers
Esslercuffi (305)
The problem is not as trivial as it might seem at first blush. The solution is a really nifty analytical tool called 'grammar'. And no, I'm not criticizing your writing.

http://en.wikipedia.org/wiki/Parsing_expression_grammar

It'd take me a week to try and explain how to do this. Luckily, Bjarne Stroustrup has already done it. If possible, get your hands on a copy of "Programming Principles and Practice using C++" and check out chapters 6 - 7. He describes how to use grammars to solve the exact problem you're doing.
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