Hello, codeforces!↵
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As you can observe from my rank, I am quite a codeforces newbie. I spend all my days on the sacred romanian OJ, Infoarena( https://www.infoarena.ro/ ), and, more recently, Kilonova( https://kilonova.ro/ ).↵
Altough the blue color is dominating my profile and I should not be taken seriously for such heresy, I want to share with the good people of codeforces an interesting problem. Please do not bully me, despite my little experience. I would be honored to hear your opinion.↵
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This is the problem:↵
You are given a string S of digits separated by the following operators: +, -, /, ^(pow), ^(xor), &, |, (, ).↵
Parentheses have biggest priority, then: '^'(pow) > '/' > '+' > '-' > '&' > '|' > '^'(xor).↵
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The task is to find out in how many ways modulo 10^9 + 7 you can rearrange the characters of the string such that the result is a givenx modulo 10^9 + 7X(X < 10).↵
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|S| <= 2 * 10 ^ 5.↵
Time limit: 0.01 seconds↵
Memory limit: common sense ↵
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I know how to solve this problem, but my solution is, as we call it in Romania, a very big "tractor" (translation for truck). I am very curious for what you come up with.↵
↵
Best wishes,↵
Geanina.↵
↵
↵
As you can observe from my rank, I am quite a codeforces newbie. I spend all my days on the sacred romanian OJ, Infoarena( https://www.infoarena.ro/ ), and, more recently, Kilonova( https://kilonova.ro/ ).↵
Altough the blue color is dominating my profile and I should not be taken seriously for such heresy, I want to share with the good people of codeforces an interesting problem. Please do not bully me, despite my little experience. I would be honored to hear your opinion.↵
↵
This is the problem:↵
You are given a string S of digits separated by the following operators: +, -, /, ^(pow), ^(xor), &, |, (, ).↵
Parentheses have biggest priority, then: '^'(pow) > '/' > '+' > '-' > '&' > '|' > '^'(xor).↵
↵
The task is to find out in how many ways modulo 10^9 + 7 you can rearrange the characters of the string such that the result is a given
↵
|S| <= 2 * 10 ^ 5.↵
Time limit: 0.01 seconds↵
Memory limit: common sense ↵
↵
I know how to solve this problem, but my solution is, as we call it in Romania, a very big "tractor" (translation for truck). I am very curious for what you come up with.↵
↵
Best wishes,↵
Geanina.↵
↵
