数学方法转化限制条件(使大于小于等于号左右互为相反数,变成绝对值)+加减交错法构造博弈论下界推出最优解再用限制代入:AT_agc056_d
https://vj.imken.moe/contest/600552#problem/G考虑对题目进行转化L≤Sa≤RL\leS_a\leRL≤Sa≤R2L≤2Sa≤2R2L\le2S_a\le2R2L≤2Sa≤2R2L+Sb≤Sa+S≤2R+Sb2L+S_b\leS_a+S\le2R+S_b2L+Sb≤Sa+S≤2R+Sb2L−S≤Sa−Sb≤2R−S2L-S\leS_a-S_b\le2R-S