import sys

def main():
    lines = [line.strip() for line in sys.stdin if line.strip()]
    if not lines:
        print(0)
        return
    
    n = int(lines[0])
    if n != 3:
        print(0)
        return
    
    rest = lines[1:]
    if len(rest) != 3:
        if len(rest) == 1:
            parts = rest[0].split()
            if len(parts) == 3:
                print('"assert"')
                return
            else:
                print('"assert"')
                return
        else:
            print('"assert"')
            return
    
    try:
        a = int(rest[0])
        b = int(rest[1])
        c = int(rest[2])
    except ValueError:
        print('"assert"')
        return
    
    sums = [a + b, a + c, b + c]
    unique_sums = sorted(list({x for x in sums}), reverse=True)
    
    if len(unique_sums) >= 2:
        print(unique_sums[1])
    else:
        print(unique_sums[0])

if __name__ == "__main__":
    main()