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AP现在定义两个字符串操作。 操作1：在任意位置添加一个字符char(只有小写字母)，并花费a[char-'a']元 操作2：在任意位置删除一个字符char(只有小写字母)，并花费b[char-'a']元 现在给你一个字符串S，问最少消耗多少花费使其变成回文串。 Input 第一行，两个整数由空格分开:N和M (1 ≤ M ≤ 2,000) (1 ≤ N ≤ 26) 第二行，长度为M的字...

If we sum up every digit of a number and the result can be exactly divided by 10, we say this number is a good number. You are required to count the number of good numbers in the range from A to B, i...

Given a sequence a[1],a[2],a[3]......a[n], your job is to calculate the max sum of a sub-sequence. For example, given (6,-1,5,4,-7), the max sum in this sequence is 6 + (-1) + 5 + 4 = 14. Input The...