Code example for Stack

Methods: clear, push

0
        } 
    } 
 
    private void doOpChar(char op) {
        if (isInEquals) {
            stack.clear();
            isInEquals = false;
        } 
        stack.push(result);
        doLastOp(); 
        lastOp = op;
        tvOp.setText(String.valueOf(lastOp));
    } 
 
    private void doLastOp() { 
        isRestart = true;
        if (lastOp == '\0' || stack.size() == 1) {
            return; 
        } 
 
        String valTwo = stack.pop();