I am still having trouble w/ my function to convert infix to postfix notation. I have figured out how to convert equations with two numbers and one operand successfully and how to work w/ numbers that are > 1 digit, but the algortihm does not work correctly for equations w/ more than one operator e.g. (1-2)*(4+5) which should output 1 2 - 4 5 + * instead outputs 1 2 -. I am pretty sure it is the result of pointers being incremented to far so they point to '\0', but I am not sure how to fix it.

For the example above, *lastwritteninoq = '\0' when *currentpointer = ')' and from there nothing can be added to the outputqueue. I beleive a similar thing happens w/ oqpointer but I am stumped on how to fix it.Code://Pass in inputqueue for reading, and outputqueue for writing int ConvertToPolishNotation(char inputqueue[], char outputqueue[]) { char *lastwritteninoq = outputqueue, operatorqueue[50]; memset(operatorqueue,0, 50); char *currentpointer = inputqueue, *oqpointer = operatorqueue; int counter = 0, nextToken = 0; while (*currentpointer != '\0') { /*or whatever your end of input is*/ while (isdigit(*currentpointer)) { *lastwritteninoq++ = *currentpointer++; nextToken = 1; } /*or if you're reading an entire number, += number_of_digits_read */ if (*currentpointer=='+' || *currentpointer == '-' || *currentpointer=='*' || *currentpointer == '/') { *oqpointer++ = *currentpointer++; } else if (*currentpointer=='(') {//Push it onto stack *oqpointer++ = *currentpointer++; } else if (*currentpointer==')') { while ((*oqpointer != '(') && (*currentpointer != '\0') && (counter < 50) && (*currentpointer==')')) { //Until the token at the top of the stack is a left parenthesis, //pop operators off the operatorqueue onto the outputqueue *lastwritteninoq++ = *(--oqpointer); counter++; lastwritteninoq++; currentpointer++; } if (counter == 50) { //BRACKET MISMATCH MessageBox(NULL, "Bracket Mismatch", "Error", MB_OK); return -1; } //Pop the left parenthesis from the operatorqueue, but not onto the outputqueue. *--oqpointer = '0'; } //END BRACKET if (nextToken) { //Space-seperate each token, this helps w/ multiple *lastwritteninoq++ = ' '; //digits nextToken = 0; } } //NO MORE TOKENS oqpointer = operatorqueue; //Reset pointer //While there are still operator tokens in the stack: while (*oqpointer != '\0') { if ((*oqpointer == ')') || (*oqpointer == '(')) {//BRACKET MessageBox(NULL, "Bracket Mismatch", "Error", MB_OK); return -1; } else if (*oqpointer == '0') oqpointer++; else { oqpointer++; *lastwritteninoq++ = *(--oqpointer); lastwritteninoq++; *oqpointer = '0'; } } return 1; }