#include <algorithm>
#include <iostream>
#include <string>
using namespace std;
int main() {
auto x = "foobar"s;
const auto value = "foo"s;
const auto it = search(cbegin(x), cend(x), cbegin(value), cend(value));
if(it != cend(x)) {
x.replace(it, next(it, value.size()), crbegin(value), crend(value));
}
cout << x << endl;
}
I2luY2x1ZGUgPGFsZ29yaXRobT4KI2luY2x1ZGUgPGlvc3RyZWFtPgojaW5jbHVkZSA8c3RyaW5nPgoKdXNpbmcgbmFtZXNwYWNlIHN0ZDsKCmludCBtYWluKCkgewoJYXV0byB4ID0gImZvb2JhciJzOwoJY29uc3QgYXV0byB2YWx1ZSA9ICJmb28iczsKCWNvbnN0IGF1dG8gaXQgPSBzZWFyY2goY2JlZ2luKHgpLCBjZW5kKHgpLCBjYmVnaW4odmFsdWUpLCBjZW5kKHZhbHVlKSk7CgoJaWYoaXQgIT0gY2VuZCh4KSkgewoJCXgucmVwbGFjZShpdCwgbmV4dChpdCwgdmFsdWUuc2l6ZSgpKSwgY3JiZWdpbih2YWx1ZSksIGNyZW5kKHZhbHVlKSk7CQoJfQoJY291dCA8PCB4IDw8IGVuZGw7Cn0=