title: parsing math expression in python and solving to find an answer
body: <p>I am quite new to programming. This is in relation to python. So the idea is to take an expression such as 3/5 or, at most, 3/5*2(at most two operators, note that the operators can be any of +,-,/,*) and solve it. White space can exist anywhere within the expression.</p>
  
  <p>The user enters the expression, say 3/5, and the program needs to solve the expression and display the answers. What I have tried is below. Note, I only have attempted the first part, once I can properly split the original expression that the user enters(which would be a string), creating functions would be the easy part:</p>
  
  <pre><code>expres= str(input("something:"))
  
  ssplit= hit.partition("/")
  onec= int((ssplit[0].lstrip()).rstrip())
  twoc= (ssplit[1].lstrip()).rstrip()
  threec= int((huns[2].lstrip()).rstrip())
  
  
  print(onec,"...",twoc,"...",threec) #just a debug test print
  </code></pre>
  
  <p>So above, I can take an expression like 3/5 and split it into three separate strings:3 , /, and 5. I can also remove all whitespace before and after the operators/operands. I am having problems with splitting expressions like 4/5+6, Because I can't put code in for ssplit[3] or ssplit[4] and then enter an expression like 3/5, because it won't be defined. Basically I needed you help to find out how to split an expression like 3/4-6,etc. I also need help with the line "<code>ssplit= hit.partition("/")</code>" so that it will look at the entered expression and work with +,-, and * as well. Any and all help is appreciated. Also if my code above looks nasty and inefficient please give me criticism. Thanks!</p>
  
  <p>Note I can't, and wouldn't want to use eval.
  Order of operations is required.
  I cant use complicated commands. I need to keep it simple, the most I can use is string libraries, converting between strings/integers/floats etc. and if,and,etc. statements. I can also use functions.</p>