8

func myAtoi(str string) int {
    var i int
    var tag = 0
    var a = 0
    var j int
    const (
        INT_MAX int = 1<<31-1
        INT_MIN int = -1<<31 
        )  
    for i = 0 ;i<len(str);i++{
        if str[i]>='0'&&str[i]<='9'{
          break  
        }else if str[i]=='+' {
            i++    
            break    
        }else if str[i]=='-'{
            i++
           tag=1
            break
        }else if str[i] ==' '{
          i=i
        }else {
            return 0
        }
    }
    for j = i ;j<len(str);j++{
        if str[j]>'9' || str[j]<'0'{
            break
        }
    }
    for k:=i; k<j; k++{
      
       
        if tag==0{
       d:=0  
       
        d=int(str[k]-'0')
        a=a*10+d
        if a>INT_MAX{
            return INT_MAX
        }}else {
           e:=0
            e=int(str[k]-'0')
 
            a=a*10-e
        if a<INT_MIN{
               return INT_MIN
    }
        }}
              

        
    
    
    return a
}