Did they type the letters in order
A command palette matches what someone typed against a command name: the letters have to appear in order, but not next to each other.
- Every character of the typed text must appear in the command, in the same order.
- Characters may be spread out — gaps in the command are fine.
- Typing nothing matches every command.
- Matching is exact, character for character; nothing is case-folded here.
typedInOrder(typed: string, command: string) → bool
C++ needs a compiler and Drill does not host one yet, so this page is the reference rather than an exercise: the problem, worked examples, and the solution in full. To type it out, the same problem runs in Python.
Where you start
bool typedInOrder(std::string typed, std::string command) {
}Worked examples
| Call | Result |
|---|---|
typedInOrder(std::string("abc"), std::string("axbxc")) | true |
typedInOrder(std::string("acb"), std::string("axbxc")) | false |
typedInOrder(std::string(""), std::string("anything")) | true |
typedInOrder(std::string("abc"), std::string("abc")) | true |
Hint
One index walks the typed text, one walks the command. Advance the command index every step, and the typed index only when the two characters agree.
Reference solution in C++
bool typedInOrder(std::string typed, std::string command) {
size_t i = 0;
for (char ch : command) {
if (i < typed.size() && typed[i] == ch) i++;
}
return i == typed.size();
}