[{"sectionTitle":"题目描述","type":"Text","text":"原题来自：POJ 2891\r\n\r\n给定 $2n$ 个正整数 $a_1,a_2,\\cdots ,a_n$ 和 $m_1,m_2,\\cdots ,m_n$，求一个最小的正整数 $x$，满足 $\\forall i\\in[1,n],x\\equiv a_i\\ (\\bmod m_i\\ )$，或者给出无解。","subType":"markdown"},{"sectionTitle":"输入格式","type":"Text","text":"多组数据。\r\n\r\n每组数据第一行一个整数 $n$； \r\n接下来 $n$ 行，每行两个整数 $m_i,a_i$。","subType":"markdown"},{"sectionTitle":"输出格式","type":"Text","text":"对于每组数据，若无解，输出 $-1$；否则输出一个非负整数，若有多解，输出最小的满足条件的答案。","subType":"markdown"},{"sectionTitle":"样例","type":"Sample","text":"","subType":"markdown","payload":["2\n8 7\n11 9","31"]},{"sectionTitle":"数据范围与提示","type":"Text","text":"对于全部数据，所有的输入都是非负的，并且可以用 $64$ 位有符号整数表示。保证 $1\\le n\\le 10^5,m_i\\gt a_i$。","subType":"markdown"}]