{"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":"\u003cdiv\u003e \n \u003cspan\u003e\u003cspan\u003e\u003cspan\u003e\u003cspan\u003e\u003cspan\u003e\u003cspan\u003e欢迎来到西南交大ACM协会\u003c/span\u003e\u003cspan\u003e第一次训练\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\n\u003c/div\u003e \n\u003cdiv\u003e \n \u003cspan\u003e\u003cspan\u003e\u003cspan\u003e\u003cspan\u003e\u003cspan\u003e\u003cspan\u003e现在给你一个数字n\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e, \n \u003cspan\u003e\u003cspan\u003e\u003cspan\u003e\u003cspan\u003e\u003cspan\u003e\u003cspan\u003e要你求出\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e 1 + 2 + 3 + ... + n\u0026nbsp; \n \u003cspan\u003e\u003cspan\u003e\u003cspan\u003e\u003cspan\u003e\u003cspan\u003e\u003cspan\u003e的和是多少\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\n\u003c/div\u003e"}},{"title":"Input","value":{"format":"HTML","content":"\u003cp\u003e \u003cspan\u003e\u003cspan\u003e\u003cspan\u003e\u003cspan\u003e\u003cspan\u003e多组输入,每一组输入会包含一个整数n\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e"}},{"title":"Output","value":{"format":"HTML","content":"\u003cp\u003e 对于每一组输入,单独一行输出和,答案后再输出一行空行\u003cspan\u003e。和的数值最大不会超过一个32位的int类型。\u003c/span\u003e \u0026nbsp; \u0026nbsp;\u003c/p\u003e"}},{"title":"Sample Input","value":{"format":"HTML","content":"\u003cpre\u003e\n60000\n100\u003c/pre\u003e"}},{"title":"Sample Output","value":{"format":"HTML","content":"\u003cpre\u003e\n1800030000\n\n5050\u003c/pre\u003e"}}]}