[Python 3] with explanation.
Suppose we have a coin of value c[i], we can use this coin to extend current consecutive values, only if we have already built consecutive values no less than c
Suppose we have a coin of value ```c[i]```, we can use this coin to extend current consecutive values, only if we have already built consecutive values no less than ```c[i] - 1```. \n\nSo just sort coins by value, for each ```coin[i]```, check if ```c[i]``` satisfies ```c[i] <= cur_max + 1```. If so, increase the maximum value from ```cur_max``` to ```cur_max + coin[i]```, otherwise, return ```c[i] + 1``` (No need to try any following coins because coin with larger value can not cover ```cur_max + 1``` neither). \n\n* For example:```\nvalues = [0,1,2,3,4,5,6],\nnew_c = 7```\nTherefore we can build ```[7, 8, ... , 13]``` with ```new value = 7```, now the consecutive value list is ```[0, 1, ... , 13]```\n\nHowever, if the new value is 2 more larger than the maximum number, we can not find a way to fill the ```value = max_values + 1```\n\n* For example:```\nvalues = [0,1,2,3,4,5,6],\nnew_c = 8```\nIn this case, ```max_value = 6```, we cant fit the value 7 with current coins, meaning the maximum value we can reach is max_value, ```ans = max_value + 1``` (including 0)\n\n```\ndef getMaximumConsecutive(self, coins: List[int]) -> int:\n    coins.sort()\n    cur = 0\n    for idx in range(len(coins)):\n        if coins[idx] - 1 > cur:\n            break\n        cur += coins[idx]\n    return cur + 1\n```
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