{"raw_statement":[{"iden":"problem statement","content":"Given are integers $a$, $b$, $c$, and $d$.  \nWe will choose integers $x$ and $y$ such that $a ≤ x ≤ b$ and $c ≤ y ≤ d$. Find the maximum possible value of $x - y$ here."},{"iden":"constraints","content":"*   All values in input are integers.\n*   $-100 ≤ a ≤ b ≤ 100$\n*   $-100 ≤ c ≤ d ≤ 100$"},{"iden":"input","content":"Input is given from Standard Input in the following format:\n\n$a$ $b$\n$c$ $d$"},{"iden":"sample input 1","content":"0 10\n0 10"},{"iden":"sample output 1","content":"10\n\n$(x, y) = (10, 0)$ achieves the maximum value $x - y = 10$."},{"iden":"sample input 2","content":"\\-100 -100\n100 100"},{"iden":"sample output 2","content":"\\-200"},{"iden":"sample input 3","content":"\\-100 100\n-100 100"},{"iden":"sample output 3","content":"200"}],"translated_statement":null,"sample_group":[],"show_order":["default"],"formal_statement":null,"simple_statement":null,"has_page_source":true}