Логика и программирование

#include <iostream>
#include <conio.h>

using namespace std;

int main()
{
int a=0,b=0,c;char text[64];bool ma=0,mb=0;
cin>>text;
for(int i=0,j=0;i<strlen(text);i++)
{
if (i==0&&text[i]=='-') ma=1;
if (text[i]>='0'&&text[i]<='9')
if (j) {b*=10;b+=text[i]-'0';}
else {a*=10;a+=text[i]-'0';}
if (text[i]=='+') {j=1;c=0;if (text[i+1]=='-') mb=1;}
if (text[i]=='-'&&i>0&&j==0) {j=1;c=1;if (text[i+1]=='-') mb=1;}
if (text[i]=='*') {j=1;c=2;if (text[i+1]=='-') mb=1;}
if (text[i]=='/') {j=1;c=3;if (text[i+1]=='-') mb=1;}
}
if (ma) a=-a;if (mb) b=-b;
while(true) {if (c==0) {c=a+b;break;} if (c==1) {c=a-b;break;} if (c==2) {c=a*b;break;} if (c==3) {c=a/b;break;}}
cout<<"="<<c;
getch();
return 0;
}