Cómo obtener números de la cadena en CPP

// An easier way to extract each character would be:

string s = "abcde"; 
 
for (int i=0; i<s.size(); i++) { 
    cout << s[i];  
} 
// To test if a particular character is an integer, you would do this:

//test if s[i] is an int from 0-9 
if (s[i] <= '9' && s[i] >= '0') { 
    return true; 
} 
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