{"raw_statement":[{"iden":"problem statement","content":"We have a number line. Takahashi painted some parts of this line, as follows:\n\n*   First, he painted the part from $X=L_1$ to $X=R_1$ red.\n*   Next, he painted the part from $X=L_2$ to $X=R_2$ blue.\n\nFind the length of the part of the line painted both red and blue."},{"iden":"constraints","content":"*   $0\\leq L_1<R_1\\leq 100$\n*   $0\\leq L_2<R_2\\leq 100$\n*   All values in input are integers."},{"iden":"input","content":"Input is given from Standard Input in the following format:\n\n$L_1$ $R_1$ $L_2$ $R_2$"},{"iden":"sample input 1","content":"0 3 1 5"},{"iden":"sample output 1","content":"2\n\nThe part from $X=0$ to $X=3$ is painted red, and the part from $X=1$ to $X=5$ is painted blue.\nThus, the part from $X=1$ to $X=3$ is painted both red and blue, and its length is $2$."},{"iden":"sample input 2","content":"0 1 4 5"},{"iden":"sample output 2","content":"0\n\nNo part is painted both red and blue."},{"iden":"sample input 3","content":"0 3 3 7"},{"iden":"sample output 3","content":"0\n\nIf the part painted red and the part painted blue are adjacent to each other, the length of the part painted both red and blue is $0$."}],"translated_statement":null,"sample_group":[],"show_order":["default"],"formal_statement":null,"simple_statement":null,"has_page_source":true}