// Guess which symbol to use for derivative, integral, etc. #include "stdafx.h" #include "defs.h" void guess(void) { if (find(stack[tos - 1], symbol(SYMBOL_X))) push_symbol(SYMBOL_X); else if (find(stack[tos - 1], symbol(SYMBOL_T))) push_symbol(SYMBOL_T); else push_symbol(SYMBOL_X); }