+-,但是让计算机去运算就有歧义了。上面的式子是很简单的,实际可以遇到很多层括号,计算机不会去括号的。因此就有了波兰式和逆波兰式。 波兰式和逆波兰式里,没有括号,计算没有歧义。 波兰式,也称为前缀表达式,即运算符在前面,数字在后面,上面的计算式转换成波兰式后为+2*3-49。 逆波兰式,也称为后缀表达式,即运算符都在后面,数字在前面,上面的计算式转换成逆波兰式后为2349-*","https://file.jishuzhan.net/article/1703697331779538946/64118e8da20f48d185e2829c79023df5.png",2,"1691343973051797506","PleaseBrave","https://file.jishuzhan.net/user/1691343973051797506/head.png",[21,24,27,30,31],{"id":22,"name":23},97,"算法",{"id":25,"name":26},129,"leetcode",{"id":28,"name":29},4269,"栈",{"id":7,"name":8},{"id":32,"name":33},12077,"逆波兰式",1695028071000,"169850",false,["Reactive",38],{"$sisPC2":36},["Set"],["ShallowReactive",41],{"KoELoR-VMpikMPJp97vzmVENLp6AUOjhjsw17FtXlJs":-1,"dKZP329yymr0x8NROKmjm680Z22i-wEqEjZzIrHbhMo":-1,"QQ0l75pFjU8UXsEhnKmSIQSC6e4YoQ4UYlg46gKf0Z4":-1},true,"/tag/12076"]