Traveling Budget

You planned a trip using trains and buses. The train fare will be A yen (the currency of Japan) if you buy ordinary tickets along the way, and B yen if you buy an unlimited ticket. Similarly, the bus fare will be C yen if you buy ordinary tickets along the way, and D yen if you buy an unlimited ticket.

Find the minimum total fare when the optimal choices are made for trains and buses.

Constraints

• 1 \leq A \leq 1 000
• 1 \leq B \leq 1 000
• 1 \leq C \leq 1 000
• 1 \leq D \leq 1 000
• All input values are integers.

Input

Input is given from Standard Input in the following format:

A B C D

Output

Print the minimum total fare.

Examples

Input

600 300 220 420

Output

520

Input

555 555 400 200

Output

755

Input

549 817 715 603

Output

1152

inputFormat

input values are integers.

Input

Input is given from Standard Input in the following format:

A B C D

outputFormat

Output

Print the minimum total fare.

Examples

Input

600 300 220 420

Output

520

Input

555 555 400 200

Output

755

Input

549 817 715 603

Output

1152

样例

549
817
715
603

1152