2042. Check if Numbers Are Ascending in a Sentence

class Solution {
public:
    bool areNumbersAscending(string s) {
        
        int chk=-1;
       
       for(int i=0; i<s.size(); i++)
        {
             string str="";
             int p=0;
            while(s[i]>=48 && s[i]<=57)
               {
                   str+=s[i];
                   i++;
                   p=1;
               }
         if(p==1)
         {
             if(stoi(str)>chk)
             chk=stoi(str);
             else
             return false;
             
         }
             
        }
       return true; 
    }
};