"""练习 24 进阶版：用解包、min 和算术表达式实现计数原理。"""
a, b, c, d = map(int, input().split())
if min(a, b, c, d) < 0:
    raise ValueError("选项数量不能为负数")

print("addition principle:", a + b)
print("multiplication principle:", c * d)