Просмотр кода страницы Часто используемые фрагменты

== Split и join ==

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 vector<string> split(string &line) {
     vector<string> words;
     string word;
     for (char c : line) {
         if (c != ' ') {
             word += c;
         } else if (!word.empty()) {
             words.push_back(word);
             word.clear();
         }
     }
     if (!word.empty())
         words.push_back(word);
     return words;
 }

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 string join(vector<string> &words) {
     string line;
     for (int i = 0; i < words.size(); i++)
         line += words[i] + (i + 1 < words.size() ? " " : "");
     return line;
 }

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 vector<string> split(string &line, const string &separators) {
     vector<string> words;
     string word;
     for (char c : line) {
         if (separators.find(c) == -1) {
             word += c;
         } else if (!word.empty()) {
             words.push_back(word);
             word.clear();
         }
     }
     if (!word.empty())
         words.push_back(word);
     return words;
 }

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 string join(vector<string> &words, const string &separator) {
     string line;
     for (int i = 0; i < words.size(); i++)
         line += words[i] + (i + 1 < words.size() ? separator : "");
     return line;
 }

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== Перевод систем счисления ==

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 long long toDec(string s, int base) {
     static const string DIGITS = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
     long long res = 0;
     for (char c : s)
         res = res * base + DIGITS.find(c);
     return res;
 }
    
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 string fromDec(long long n, int base) {
     static const string DIGITS = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
     string res;
     while (n >= base) {
         res += DIGITS[n % base];
         n /= base;
     }
     res += DIGITS[n];
     reverse(res.begin(), res.end());
     return res;
 }

|}

== Римская система счисления ==

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 string toRoman(int n) {
     static const vector<pair<string, int>> CODES = {
         {"M", 1000}, {"CM", 900}, {"D", 500}, {"CD", 400},
         {"C", 100}, {"XC", 90}, {"L", 50}, {"XL", 40},
         {"X", 10}, {"IX", 9}, {"V", 5}, {"IV", 4}, {"I", 1}
     };
     
     string res;
     for (auto &[code, value] : CODES) {
         while (n >= value) {
             n -= value;
             res += code;
         }
     }
     return res;        
 }

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 int fromRoman(const string &s) {
     static const vector<pair<string, int>> CODES = {
         {"M", 1000}, {"CM", 900}, {"D", 500}, {"CD", 400},
         {"C", 100}, {"XC", 90}, {"L", 50}, {"XL", 40},
         {"X", 10}, {"IX", 9}, {"V", 5}, {"IV", 4}, {"I", 1}
     };
     
     int pos = 0, res = 0;
     for (auto &[code, value] : CODES) {
         while (s.substr(pos, code.size()) == code) {
             pos += code.size();
             res += value;
         }
     }
     return res;
 }

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