public void SubmitScore(int playerScore) {
    PlayFabClientAPI.UpdatePlayerStatistics(new UpdatePlayerStatisticsRequest {
        Statistics = new List<StatisticUpdate> {
            new StatisticUpdate {
                StatisticName = "HighScore",
                Value = playerScore
            }
        }
    }, result=> OnStatisticsUpdated(result), FailureCallback);
}

private void OnStatisticsUpdated(UpdatePlayerStatisticsResult updateResult) {
    Debug.Log("Successfully submitted high score");
}

private void FailureCallback(PlayFabError error){
    Debug.LogWarning("Something went wrong with your API call. Here's some debug information:");
    Debug.LogError(error.GenerateErrorReport());
}

//Get the players with the top 10 high scores in the game
public void RequestLeaderboard() {
    PlayFabClientAPI.GetLeaderboard(new GetLeaderboardRequest {
            StatisticName = "HighScore",
            StartPosition = 0,
            MaxResultsCount = 10
    }, result=> DisplayLeaderboard(result), FailureCallback);
}

private void FailureCallback(PlayFabError error){
    Debug.LogWarning("Something went wrong with your API call. Here's some debug information:");
    Debug.LogError(error.GenerateErrorReport());
}