年少轻狂不懂胜者为王年少轻狂该懂败者为寇
[nián shăo qīng kuáng bù dŏng shèng zhĕ wéi wáng nián shăo qīng kuáng gāi dŏng bài zhĕ wéi kòu]
In youthful recklessness, we don’t understand that winners are kings; in youth’s rashness, we should understand that losers are considered bandits. This expresses regret over youthful foolishness and an eventual realization of the harshness of social norms.