Kincow_Doki: 输入：(2*5+15)-3*2+(4+6)/2，输出为-1，答案应该是错误的，应该是这段代码有问题，只有首个数字是-号才需要这样吧 if (c == '-' && (isOperatorPre || ops.empty())) { int j = i + 1; while (j < expression.length() && (Character.isDigit(expression.charAt(j)) || '.' == expression.charAt(j))) { j++; } nums.push(new BigDecimal(expression.substring(i + 1, j)).negate()); System.out.println("333 nums top=" + nums.peek()); i = j - 1; isOperatorPre = false; }