{"trustable":true,"prependHtml":"\u003cstyle type\u003d\u0027text/css\u0027\u003e\n .input, .output {\n border: 1px solid #888888;\n }\n .output {\n margin-bottom: 1em;\n position: relative;\n top: -1px;\n }\n .output pre, .input pre {\n background-color: #EFEFEF;\n line-height: 1.25em;\n margin: 0;\n padding: 0.25em;\n }\n \u003c/style\u003e\n \u003clink rel\u003d\"stylesheet\" href\u003d\"//codeforces.org/s/96598/css/problem-statement.css\" type\u003d\"text/css\" /\u003e\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 type\u003d\"text/javascript\" async src\u003d\"https://mathjax.codeforces.org/MathJax.js?config\u003dTeX-AMS_HTML-full\"\u003e\u003c/script\u003e","sections":[{"title":"","value":{"format":"HTML","content":"\u003cp\u003ePirate John Silver has found a map depicting exactly one island in a sea. The map is a piece of cloth divided into cells: \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003en\u003c/i\u003e\u003c/span\u003e cells in height and \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003em\u003c/i\u003e\u003c/span\u003e cells in width. John Silver knows that every cell denotes either land or water, but some of the cells are erased, and now it\u0027s absolutely impossible to say what these cells represent.\u003c/p\u003e\u003cp\u003eHelp John Silver to restore the map of the island. An island is a non-empty set of land cells connected in four directions (up, down, left and right).\u003c/p\u003e"}},{"title":"Input","value":{"format":"HTML","content":"\u003cp\u003eThe first line contains two integers \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003en\u003c/i\u003e\u003c/span\u003e and \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003em\u003c/i\u003e\u003c/span\u003e \u003cspan class\u003d\"tex-span\"\u003e(1 ≤ \u003ci\u003en\u003c/i\u003e, \u003ci\u003em\u003c/i\u003e ≤ 50)\u003c/span\u003e\u0026nbsp;— the sizes of the map.\u003c/p\u003e\u003cp\u003eEach of the next \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003en\u003c/i\u003e\u003c/span\u003e lines contains \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003em\u003c/i\u003e\u003c/span\u003e characters and describes the map. A character is equal to «\u003cspan class\u003d\"tex-font-style-tt\"\u003e#\u003c/span\u003e» if this cell is a water cell, «\u003cspan class\u003d\"tex-font-style-tt\"\u003e.\u003c/span\u003e» if it\u0027s a land cell, and «\u003cspan class\u003d\"tex-font-style-tt\"\u003e?\u003c/span\u003e» if this cell is erased.\u003c/p\u003e\u003cp\u003eIt\u0027s guaranteed that the input contains at least one character «\u003cspan class\u003d\"tex-font-style-tt\"\u003e.\u003c/span\u003e» and at least one character «\u003cspan class\u003d\"tex-font-style-tt\"\u003e?\u003c/span\u003e».\u003c/p\u003e"}},{"title":"Output","value":{"format":"HTML","content":"\u003cp\u003eIf it\u0027s not possible to restore the map so that it would depict exactly one island, output «\u003cspan class\u003d\"tex-font-style-tt\"\u003eImpossible\u003c/span\u003e».\u003c/p\u003e\u003cp\u003eIf the map can be restored in a unique way, output \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003en\u003c/i\u003e\u003c/span\u003e lines of \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003em\u003c/i\u003e\u003c/span\u003e characters in the same format as they are in the input, but replacing «\u003cspan class\u003d\"tex-font-style-tt\"\u003e?\u003c/span\u003e» with «\u003cspan class\u003d\"tex-font-style-tt\"\u003e.\u003c/span\u003e» or «\u003cspan class\u003d\"tex-font-style-tt\"\u003e#\u003c/span\u003e».\u003c/p\u003e\u003cp\u003eAnd if there are several correct ways to restore the map, output «\u003cspan class\u003d\"tex-font-style-tt\"\u003eAmbiguous\u003c/span\u003e».\u003c/p\u003e"}},{"title":"Examples","value":{"format":"HTML","content":"\u003ctable class\u003d\u0027vjudge_sample\u0027\u003e\n\u003cthead\u003e\n \u003ctr\u003e\n \u003cth\u003eInput\u003c/th\u003e\n \u003cth\u003eOutput\u003c/th\u003e\n \u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\u003cpre\u003e5 7\n\n#######\n\n#..#..#\n\n#..?..#\n\n#..#..#\n\n#######\n\u003c/pre\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cpre\u003e#######\n\n#..#..#\n\n#.....#\n\n#..#..#\n\n#######\n\u003c/pre\u003e\u003c/td\u003e\n \u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n"}},{"title":"","value":{"format":"HTML","content":"\u003ctable class\u003d\u0027vjudge_sample\u0027\u003e\n\u003cthead\u003e\n \u003ctr\u003e\n \u003cth\u003eInput\u003c/th\u003e\n \u003cth\u003eOutput\u003c/th\u003e\n \u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\u003cpre\u003e5 7\n\n#######\n\n#...#.#\n\n#.?.?.#\n\n#.#...#\n\n#######\n\u003c/pre\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cpre\u003eAmbiguous\n\u003c/pre\u003e\u003c/td\u003e\n \u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n"}},{"title":"","value":{"format":"HTML","content":"\u003ctable class\u003d\u0027vjudge_sample\u0027\u003e\n\u003cthead\u003e\n \u003ctr\u003e\n \u003cth\u003eInput\u003c/th\u003e\n \u003cth\u003eOutput\u003c/th\u003e\n \u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\u003cpre\u003e5 7\n\n#######\n\n#.#.#.#\n\n#.#?#.#\n\n#.#.#.#\n\n#######\n\u003c/pre\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cpre\u003eImpossible\n\u003c/pre\u003e\u003c/td\u003e\n \u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n"}}]}