include

include

using namespace std;

int main() { string str1 = "This is a test string"; string str2 = "test"; size_t found = str1.find(str2);

if (found != string::npos) {
    cout << "First occurrence is at position: " << found << endl;
} else {
    cout << "The sub-string is not found" << endl;
}

return 0;

}