how can i find out a substring of minimum length having at least k times same character(for example k times a)of a string(please in C)
how can i find out a substring of minimum length having at least k times same character(for example k times a)of a string(please in C)
№ | Пользователь | Рейтинг |
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1 | tourist | 3690 |
2 | jiangly | 3647 |
3 | Benq | 3581 |
4 | orzdevinwang | 3570 |
5 | Geothermal | 3569 |
5 | cnnfls_csy | 3569 |
7 | Radewoosh | 3509 |
8 | ecnerwala | 3486 |
9 | jqdai0815 | 3474 |
10 | gyh20 | 3447 |
Страны | Города | Организации | Всё → |
№ | Пользователь | Вклад |
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1 | maomao90 | 174 |
2 | awoo | 164 |
3 | adamant | 163 |
4 | TheScrasse | 159 |
5 | nor | 157 |
6 | maroonrk | 155 |
7 | -is-this-fft- | 152 |
8 | Petr | 146 |
8 | orz | 146 |
10 | BledDest | 145 |
Название |
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Prefix sum the number of occurrences of character c. Then do the binary search for every s[i] and find prefix sum with biggest index j such that d[i]-d[j]>=k (if d[] is prefix sum). Answer is minimum of such i-j+1.
what is prefix sum please?
Prefix sum is array that for each prefix_sum[i] counts (in this case) number of character c from 0 (if string is 0-indexed) to i. How we do that, well prefix_sum[i]=prefix_sum[i-1]. And if s[i] is certain character that we want, increment prefix_sum[i] by 1.