ATOI.cpp

class Solution {
public:
    int myAtoi(string str) {
        long temp = 0;
        int i = 0, sign = 1;
        
        while(str[i] == ' ')
        {
            i++;
        }
        
        if(str[i] == '-'){
            sign = -1;
            i++;
        }
        else if(str[i] == '+')
            i++;
        
        while(str[i] - '0' >=0 && str[i] - '0' <=9)
        {
            temp = temp*10 + (str[i] - '0');
            if(sign>0 && temp>=INT_MAX)
                return INT_MAX;
            if(sign<0 && -temp <=INT_MIN)
                return INT_MIN;
            i++;
        }        
        return temp*sign;
    }
};