{"trustable":false,"prependHtml":"\u003cscript\u003e window.katexOptions \u003d { disable: true }; \u003c/script\u003e\n\u003cscript type\u003d\"text/x-mathjax-config\"\u003e\n MathJax.Hub.Config({\n tex2jax: {\n inlineMath: [[\u0027$$$\u0027,\u0027$$$\u0027], [\u0027$\u0027,\u0027$\u0027]],\n displayMath: [[\u0027$$$$$$\u0027,\u0027$$$$$$\u0027], [\u0027$$\u0027,\u0027$$\u0027]]\n }\n });\n\u003c/script\u003e\n\u003cscript async src\u003d\"https://mathjax.codeforces.org/MathJax.js?config\u003dTeX-AMS-MML_HTMLorMML\" type\u003d\"text/javascript\"\u003e\u003c/script\u003e","sections":[{"title":"","value":{"format":"HTML","content":"\u003cpre\u003e\nBaiXuejie found himself studying in a strange college which has all its’teaching buildings regular hexagonal prisms. These buildings are arranged in two rows, and each of them has its own number. Every building has channels between the building on its’ north side and the one on its’ east side.(North points up ,and south points down.West points left, and east points right.) Each channel is just one way through, only can get through from a building with a small number to a larger one.\u003c/pre\u003e \n\u003cpre\u003e\nBaiXuejie has two classes every morning. He has to have his second class in another building. If we had knew the two buildings he need to have his classes, how many kinds of ways can he choose to get to the second building from the first one? \u003c/pre\u003e \n\u003cp\u003e \u003cimg src\u003d\"http://acm.hdu.edu.cn/../data/images/C40-1001-1.jpg\" /\u003e\u003c/p\u003e"}},{"title":"Input","value":{"format":"HTML","content":"\u003cdiv\u003e\n \u0026nbsp;The input consists of\u0026nbsp; \n \u003ci\u003eT\u003c/i\u003e\u0026nbsp;test cases. The number of test cases\u0026nbsp; \n \u003ci\u003eT\u003c/i\u003e\u0026nbsp;is given in the first line of the input. Each test case is given in a single line,each line have two interger a and b\u0026nbsp;(0\u0026lt;a\u0026lt;b\u0026lt;50)\u0026nbsp;\n\u003c/div\u003e"}},{"title":"Output","value":{"format":"HTML","content":"\u003cdiv\u003e\n Each test cases you have to output how many way Bingo from the class a to the class b. Each tast case\u0027s output in one line.\n\u003c/div\u003e"}},{"title":"Sample Input","value":{"format":"HTML","content":"\u003cdiv\u003e \n \u003cpre\u003e\n\t\u003c/pre\u003e \n \u003cdiv\u003e \n \u003cdiv\u003e\n 2\n \u003cbr /\u003e 1 2\n \u003cbr /\u003e 3 6\u0026nbsp;\n \u003c/div\u003e \n \u003c/div\u003e \n\u003c/div\u003e"}},{"title":"Sample Output","value":{"format":"HTML","content":"\u003cdiv\u003e \n \u003cpre\u003e\n\t\u003c/pre\u003e \n \u003cdiv\u003e \n \u003cdiv\u003e\n 1\n \u003cbr /\u003e 3\u0026nbsp;\n \u003c/div\u003e \n \u003c/div\u003e \n\u003c/div\u003e"}},{"title":"Hint","value":{"format":"HTML","content":"\u003cp\u003e The case 1 \u0026nbsp;2 \u0026nbsp;only have one way :1-\u0026gt;2;\u003c/p\u003e \n\u003cp\u003e The case 3 \u0026nbsp;6 \u0026nbsp;have three ways:\u003c/p\u003e \n\u003cp\u003e \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;3-\u0026gt;4-\u0026gt;6;\u003c/p\u003e \n\u003cp\u003e \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;3-\u0026gt;5-\u0026gt;6;\u003c/p\u003e \n\u003cp\u003e \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;3-\u0026gt;4-\u0026gt;5-\u0026gt;6;\u003c/p\u003e \n\u003cp\u003e \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e"}}]}