keep adding to playerprefs

I am making a game similar to something like temple run but like a platform type. I’m 90% finished on my project but i need help with the coin. I know how to use playerprefs to store data but i don’t how to add to it. what i mean by this is if the user gets like 300 coin in the first ran, it will display in the main menu. But then if the user gets like 200 in the second run it should add 200 to 300 and in the main menu it should display 500. And so on…

All you have to do for this, is read out the previous value from prefs, add to it, and then write it again. For example.

int lTotalCoins = PlayerPrefs.GetInt("TotalCoins", 0);
lTotalCoins += lCoinsCollectedThisRun;
PlayerPrefs.SetInt("TotalCoins", lTotalCoins);