XIX Open Cup named after E.V. Pankratiev. Grand Prix of America
Problem A
Solved by Kilo. 0:59 (+2)
Problem B
Unsolved.
Problem C
Unsolved.
Problem D
Solved by Weaver_zhu. 0:14 (+)
Problem E
Solved by Xiejiadong. 3:36 (+)
Problem F
Solved by Kilo_5723. 4:44 (+1)
Problem G
Solved by Weaver_zhu. 1:38 (+2)
Problem H
Unsolved.
Problem I
Unsolved.
Problem J
Solved by Xiejiadong. 0:21 (+)
题意:求 $s$ 有多少子串的子序列包含字符串 $t$ 。
题解:预处理, $s$ 中每一个位置之后第一个出现的每一个字母的位置,包含 $t$ 的子序列,从每一个位置对应地向后跳即可。
于是枚举 $s$ 的每一个开始位置包含 $t$ 的最前的位置吗,显然从这一位向后都可以作为结束位置,直接统计答案就可以了。
Problem K
Unsolved.
Problem L
Unsolved.
Problem M
Solved by Kilo_5723. 1:46 (+1)