class Solution {
public:
    int strToInt(string str) {
        double res = 0,sign = 1;
        for(int i = 0; i < str.size(); i ++){
            if (str[i] == ' ' || str[i] == '+') continue;
            if (str[i] == '-') {
                sign = -1;
                continue;
            };
            if (!(str[i] >= '0' && str[i] <= '9')) break;
            res = res * 10 + str[i] - '0';
        }
        res *= sign;
        if (res < INT_MIN) res = INT_MIN;
        if (res > INT_MAX) res = INT_MAX;
        return res;
    }
};