Files
LeetCode-Go/leetcode/0227.Basic-Calculator-II/227. Basic Calculator II.go
2021-03-11 21:51:36 +08:00

30 lines
542 B
Go

package leetcode
func calculate(s string) int {
stack, preSign, num, res := []int{}, '+', 0, 0
for i, ch := range s {
isDigit := '0' <= ch && ch <= '9'
if isDigit {
num = num*10 + int(ch-'0')
}
if !isDigit && ch != ' ' || i == len(s)-1 {
switch preSign {
case '+':
stack = append(stack, num)
case '-':
stack = append(stack, -num)
case '*':
stack[len(stack)-1] *= num
default:
stack[len(stack)-1] /= num
}
preSign = ch
num = 0
}
}
for _, v := range stack {
res += v
}
return res
}