57 lines
720 B
Go
57 lines
720 B
Go
// Package q8 implements a solution for https://leetcode.com/problems/string-to-integer-atoi/
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package q8
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const (
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MIN = -(1 << 31)
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MAX = 1<<31 - 1
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)
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func myAtoi(s string) int {
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sign := 0
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num := 0
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Loop:
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for i := range len(s) {
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c := s[i]
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switch c {
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case '-':
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if sign != 0 {
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break Loop
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}
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sign = -1
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case '+':
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if sign != 0 {
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break Loop
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}
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sign = 1
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case ' ':
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if sign != 0 {
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break Loop
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}
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default:
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if c < '0' || c > '9' {
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break Loop
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}
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if sign == 0 {
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sign = 1
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}
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num = num*10 + int(c-'0')
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if sign*num < MIN {
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num = -MIN
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break Loop
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}
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if sign*num > MAX {
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num = MAX
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break Loop
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}
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}
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}
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return sign * num
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}
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var _ = myAtoi
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