def foo(d1, d2):
result = {}
for key in d1:
if key in d2:
result[key] = d1[key] + d2[key]
return result
x = dict(
a=1, b=2, c=3, d=4,
e=5, f=6, g=7, h=8,
i=9, j=10, k=11, l=12,
m=13, n=14, o=15,
)
y = dict(
z=1, y=2, x=3, w=4,
v=5, u=6, t=7, s=8,
r=9, q=10, p=11, o=12,
)
print(sum(foo(x, y).values()))
ZGVmIGZvbyhkMSwgZDIpOgoJcmVzdWx0ID0ge30KCWZvciBrZXkgaW4gZDE6CgkJaWYga2V5IGluIGQyOgoJCQlyZXN1bHRba2V5XSA9IGQxW2tleV0gKyBkMltrZXldCgkJCQoJcmV0dXJuIHJlc3VsdAoJCnggPSBkaWN0KAoJYT0xLCBiPTIsIGM9MywgZD00LCAKCWU9NSwgZj02LCBnPTcsIGg9OCwKCWk9OSwgaj0xMCwgaz0xMSwgbD0xMiwKCW09MTMsIG49MTQsIG89MTUsCikKeSA9IGRpY3QoCgl6PTEsIHk9MiwgeD0zLCB3PTQsCgl2PTUsIHU9NiwgdD03LCBzPTgsCglyPTksIHE9MTAsIHA9MTEsIG89MTIsCikKCnByaW50KHN1bShmb28oeCwgeSkudmFsdWVzKCkpKQ==