{"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":"\u003c/div\u003e\n你需要模拟一个编辑器。\n\u003cbr\u003e编辑器的初始时,有一个空序列。\n\u003cbr\u003e有5个操作,需要完成。\n\u003cbr\u003eI x: 把x插入到光标之后\n\u003cbr\u003eD: 删除光标之前的元素\n\u003cbr\u003eL:如果光标不在最前,把光标向左移动一次\n\u003cbr\u003eR:如果光标不在最后,把光标向右移动一次\n\u003cbr\u003eQ k:设光标之前的序列为a1,a2,...,an.求个数不超过k的最大前缀和。\n\u003cbr\u003e\n\n\n"}},{"title":"Input","value":{"format":"HTML","content":"有多组测试数据\n\u003cbr\u003e每组测数据,第一行一个整数C,1\u003c\u003dC\u003c\u003d1e6,接下来C行,每行表示一个操作。\n数据保证Q操作时,k不会超过光标前面数的个数。插入的x的绝对值小于等于1000,\n"}},{"title":"Output","value":{"format":"HTML","content":"对于每个Q操作,输出相应的结果。"}},{"title":"Sample Input","value":{"format":"HTML","content":"\u003cpre\u003e\n8\nI 2\nI -1\nI 1\nQ 3\nL\nD\nR\nQ 2\n\u003c/pre\u003e"}},{"title":"Sample Output","value":{"format":"HTML","content":"\u003cpre\u003e\n2\n3\n\u003c/pre\u003e"}},{"title":"Hint","value":{"format":"HTML","content":"\u003cpre\u003e\n下图模拟样例中的过程\n\n \n \u003cimg SRC\u003d\"CDN_BASE_URL/e451000af3bd10d90df6fad8f1ba6ad6?v\u003d1586020479\"\u003e\n\n \n \u003c/pre\u003e"}}]}