n = int(input())
temp = input()
passed = []
for i in temp:
    passed.append(i)

all = map(int, input().split())
m = {'A': 0, 'B': 1, 'C': 2, 'D': 3,
     'E': 4, 'F': 5, 'G': 6, 'H': 7,
     'I': 8, 'J': 9, 'K': 10, 'L': 11,
     'M': 12}
mReverse = {j: i for i, j in m.items()}
idxPassed = []
for i in passed:
    idxPassed.append(m[i])

maximum, maximumIdx = 0, []
for idx, i in enumerate(all):
    if idx not in idxPassed:
        if i > maximum:
            maximumIdx = []
            maximum = i
            maximumIdx.append(idx)

print(mReverse[maximumIdx[0]])