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====== Quark Round 1 ======
===== A =====
==== 题意 ====
给定 $n,m$ 求满足 $i+j=n$ 且 $\lfloor i/j\rfloor+\lceil j/i\rceil=m$ 的正整数对 $(i,j)$ 的对数。
有 $10^5$ 组数据。$n,m\leq 10^7$ 。
==== 题解 ====
将 $j=n-i$ 带入第二个式子后发现是先减后增的。在极值点两侧分别二分即可。
或者分别讨论 $i