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copied!<p>If you just want to support <code>?</code>, that's pretty easy: when you encounter a <code>?</code> in the pattern, just skip ahead over one byte of input (or check for <code>isalpha</code>, if you really meant you only want to match letters).</p> <p>Edit: Assuming the more complex problem (finding a match starting at any position in the input string), you could use code something like this:</p> <pre><code>#include <string> size_t match(std::string const &pat, std::string const &target) { if (pat.size() > target.size()) return std::string::npos; size_t max = target.size()-pat.size()+1; for (size_t start =0; start < max; ++start) { size_t pos; for (pos=0; pos < pat.size(); ++pos) if (pat[pos] != '?' && pat[pos] != target[start+pos]) break; if (pos == pat.size()) return start; } return std::string::npos; } #ifdef TEST #include <iostream> int main() { std::cout << match("??cd?", "aaaacdxyz") << "\n"; std::cout << match("?bc", "abc") << "\n"; std::cout << match("ab?", "abc") << "\n"; std::cout << match("ab?", "xabc") << "\n"; std::cout << match("?cd?", "cdx") << "\n"; std::cout << match("??cd?", "aaaacd") << "\n"; std::cout << match("??????", "abc") << "\n"; return 0; } #endif </code></pre> <p>If you only want to signal a yes/no based on whether the whole pattern matches the whole input, you do pretty much the same thing, but with the initial test for <code>!=</code> instead of <code>></code>, and then basically remove the outer loop.</p>

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