Files
LeetCode-Go/leetcode/0150.Evaluate-Reverse-Polish-Notation/150. Evaluate Reverse Polish Notation.go
2021-05-31 23:40:55 +08:00

30 lines
575 B
Go

package leetcode
import (
"strconv"
)
func evalRPN(tokens []string) int {
stack := make([]int, 0, len(tokens))
for _, token := range tokens {
v, err := strconv.Atoi(token)
if err == nil {
stack = append(stack, v)
} else {
num1, num2 := stack[len(stack)-2], stack[len(stack)-1]
stack = stack[:len(stack)-2]
switch token {
case "+":
stack = append(stack, num1+num2)
case "-":
stack = append(stack, num1-num2)
case "*":
stack = append(stack, num1*num2)
case "/":
stack = append(stack, num1/num2)
}
}
}
return stack[0]
}