{"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$$\u0027]]\n }\n });\n\u003c/script\u003e\n\u003cscript type\u003d\"text/javascript\" async src\u003d\"https://mathjax.codeforces.org/MathJax.js?config\u003dTeX-AMS_HTML-full\"\u003e\u003c/script\u003e","sections":[{"title":"","value":{"format":"HTML","content":"\u003cp\u003eYou are given a binary string of length $$$n$$$ (i. e. a string consisting of $$$n$$$ characters \u0027\u003cspan class\u003d\"tex-font-style-tt\"\u003e0\u003c/span\u003e\u0027 and \u0027\u003cspan class\u003d\"tex-font-style-tt\"\u003e1\u003c/span\u003e\u0027).\u003c/p\u003e\u003cp\u003eIn one move you can swap two adjacent characters of the string. What is the lexicographically minimum possible string you can obtain from the given one if you can perform \u003cspan class\u003d\"tex-font-style-bf\"\u003eno more\u003c/span\u003e than $$$k$$$ moves? It is possible that you do not perform any moves at all.\u003c/p\u003e\u003cp\u003eNote that you can swap the same pair of adjacent characters with indices $$$i$$$ and $$$i+1$$$ arbitrary (possibly, zero) number of times. Each such swap is considered a separate move.\u003c/p\u003e\u003cp\u003eYou have to answer $$$q$$$ independent test cases.\u003c/p\u003e"}},{"title":"Input","value":{"format":"HTML","content":"\u003cp\u003eThe first line of the input contains one integer $$$q$$$ ($$$1 \\le q \\le 10^4$$$) — the number of test cases.\u003c/p\u003e\u003cp\u003eThe first line of the test case contains two integers $$$n$$$ and $$$k$$$ ($$$1 \\le n \\le 10^6, 1 \\le k \\le n^2$$$) — the length of the string and the number of moves you can perform.\u003c/p\u003e\u003cp\u003eThe second line of the test case contains one string consisting of $$$n$$$ characters \u0027\u003cspan class\u003d\"tex-font-style-tt\"\u003e0\u003c/span\u003e\u0027 and \u0027\u003cspan class\u003d\"tex-font-style-tt\"\u003e1\u003c/span\u003e\u0027.\u003c/p\u003e\u003cp\u003eIt is guaranteed that the sum of $$$n$$$ over all test cases does not exceed $$$10^6$$$ ($$$\\sum n \\le 10^6$$$).\u003c/p\u003e"}},{"title":"Output","value":{"format":"HTML","content":"\u003cp\u003eFor each test case, print the answer on it: the lexicographically minimum possible string of length $$$n$$$ you can obtain from the given one if you can perform \u003cspan class\u003d\"tex-font-style-bf\"\u003eno more\u003c/span\u003e than $$$k$$$ moves.\u003c/p\u003e"}},{"title":"Examples","value":{"format":"HTML","content":"\u003ctable class\u003d\u0027vjudge_sample\u0027\u003e\n\u003cthead\u003e\n \u003ctr\u003e\n \u003cth\u003eInput\u003c/th\u003e\n \u003cth\u003eOutput\u003c/th\u003e\n \u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\u003cpre\u003e3\n8 5\n11011010\n7 9\n1111100\n7 11\n1111100\n\u003c/pre\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cpre\u003e01011110\n0101111\n0011111\n\u003c/pre\u003e\u003c/td\u003e\n \u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n"}},{"title":"Note","value":{"format":"HTML","content":"\u003cp\u003eIn the first example, you can change the string as follows: $$$1\\underline{10}11010 \\rightarrow \\underline{10}111010 \\rightarrow 0111\\underline{10}10 \\rightarrow 011\\underline{10}110 \\rightarrow 01\\underline{10}1110 \\rightarrow 01011110$$$. \u003c/p\u003e\u003cp\u003eIn the third example, there are enough operations to make the string sorted.\u003c/p\u003e"}}]}