class Solution {
public:
    long long strToInt(string str) {
        int k=0;
       while(k<str.size()&&str[k]==' ') k++;
       int mio=1;
       if(k<str.size())
       {
           if(str[k]=='-')
           {
               mio=-1;
               k++;
           }
           else if(str[k]=='+') k++;
       }
       long long sum=0;
       while(k<str.size()&&str[k]>='0'&&str[k]<='9')
       {
           sum=sum*10+str[k]-'0';
           if(sum>INT_MAX){
               break;
           }
           k++;
       }
       sum=sum*mio;
       if(sum>INT_MAX)
       {
           sum=INT_MAX;
       }
       if(sum<INT_MIN) sum=INT_MIN;
       return sum;
    }
};