Do the situations in which the memorizer imagines himself in a competition or in front of his teacher, after sincerely dedicating his intention to Allah, make his memorization of the Qur'an an act of shirk or riya (showing off)?

Imagine, reciting the Quran in a room or in front of a female teacher does not fall under showing off (riya'), especially with sincere intention for Allah. Sincerity contradicts showing off, and showing off after completing an act of worship does not harm it. It is recommended to strive against oneself and Satan in making one's actions sincere, and not to pay attention to whispers of showing off, but rather to continue in obedience. If a Muslim fears showing off, let him say: "O Allah, I seek refuge in You from associating anything with You knowingly, and I seek Your forgiveness for what I do not know."