{"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\n\u003cscript\u003e\n window.katexOptions \u003d {\n delimiters: [\n {left: \u0027$$$$$$\u0027, right: \u0027$$$$$$\u0027, display: true},\n {left: \u0027$$$\u0027, right: \u0027$$$\u0027, display: false},\n {left: \u0027$$\u0027, right: \u0027$$\u0027, display: true},\n {left: \u0027$\u0027, right: \u0027$\u0027, display: false}\n ]\n };\n\u003c/script\u003e\n","sections":[{"title":"","value":{"format":"HTML","content":"\u003cp\u003eYou\u0027ve got an \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003en\u003c/i\u003e × \u003ci\u003em\u003c/i\u003e\u003c/span\u003e pixel picture. Each pixel can be white or black. Your task is to change the colors of as few pixels as possible to obtain a barcode picture.\u003c/p\u003e\u003cp\u003eA picture is a barcode if the following conditions are fulfilled: \u003c/p\u003e\u003cul\u003e \u003cli\u003e All pixels in each column are of the same color. \u003c/li\u003e\u003cli\u003e The width of each monochrome vertical line is at least \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003ex\u003c/i\u003e\u003c/span\u003e and at most \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003ey\u003c/i\u003e\u003c/span\u003e pixels. In other words, if we group all neighbouring columns of the pixels with equal color, the size of each group can not be less than \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003ex\u003c/i\u003e\u003c/span\u003e or greater than \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003ey\u003c/i\u003e\u003c/span\u003e. \u003c/li\u003e\u003c/ul\u003e"}},{"title":"Input","value":{"format":"HTML","content":"\u003cp\u003eThe first line contains four space-separated integers \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003en\u003c/i\u003e\u003c/span\u003e, \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003em\u003c/i\u003e\u003c/span\u003e, \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003ex\u003c/i\u003e\u003c/span\u003e and \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003ey\u003c/i\u003e\u003c/span\u003e (\u003cspan class\u003d\"tex-span\"\u003e1 ≤ \u003ci\u003en\u003c/i\u003e, \u003ci\u003em\u003c/i\u003e, \u003ci\u003ex\u003c/i\u003e, \u003ci\u003ey\u003c/i\u003e ≤ 1000;\u0026nbsp;\u003ci\u003ex\u003c/i\u003e ≤ \u003ci\u003ey\u003c/i\u003e\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThen follow \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003en\u003c/i\u003e\u003c/span\u003e lines, describing the original image. Each of these lines contains exactly \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003em\u003c/i\u003e\u003c/span\u003e characters. Character \"\u003cspan class\u003d\"tex-font-style-tt\"\u003e.\u003c/span\u003e\" represents a white pixel and \"\u003cspan class\u003d\"tex-font-style-tt\"\u003e#\u003c/span\u003e\" represents a black pixel. The picture description doesn\u0027t have any other characters besides \"\u003cspan class\u003d\"tex-font-style-tt\"\u003e.\u003c/span\u003e\" and \"\u003cspan class\u003d\"tex-font-style-tt\"\u003e#\u003c/span\u003e\".\u003c/p\u003e"}},{"title":"Output","value":{"format":"HTML","content":"\u003cp\u003eIn the first line print the minimum number of pixels to repaint. It is guaranteed that the answer exists. \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\u003e6 5 1 2\n##.#.\n.###.\n###..\n#...#\n.##.#\n###..\n\u003c/pre\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cpre\u003e11\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\u003e2 5 1 1\n#####\n.....\n\u003c/pre\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cpre\u003e5\n\u003c/pre\u003e\u003c/td\u003e\n \u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n"}},{"title":"Note","value":{"format":"HTML","content":"\u003cp\u003eIn the first test sample the picture after changing some colors can looks as follows: \u003c/p\u003e\u003ccenter\u003e \u003cpre class\u003d\"verbatim\"\u003e\u003cbr\u003e.##..\u003cbr\u003e.##..\u003cbr\u003e.##..\u003cbr\u003e.##..\u003cbr\u003e.##..\u003cbr\u003e.##..\u003cbr\u003e\u003c/pre\u003e \u003c/center\u003e\u003cp\u003eIn the second test sample the picture after changing some colors can looks as follows: \u003c/p\u003e\u003ccenter\u003e \u003cpre class\u003d\"verbatim\"\u003e\u003cbr\u003e.#.#.\u003cbr\u003e.#.#.\u003cbr\u003e\u003c/pre\u003e \u003c/center\u003e"}}]}