1212 幂次方：正整数用 2 的幂次方表示，附 C++ 代码解析

```cpp #include <iostream> #include <string> using namespace std; string dfs(int n) { if (n == 0) return "0"; if (n == 1) return "2(0)"; if (n == 2) return "2"; string res = ""; int power = 0; while (n > 0) { if (n & 1) { string term; if (power == 0) term = "2(0)"; else if (power == 1) term = "2"; else term = "2(" + dfs(power) + ")"; if (res.empty()) res = term; else res = term + "+" + res; } n >>= 1; power++; } return res; } int main() { int n; cin >> n; cout << dfs(n) << endl; return 0; } ``` ######[AI问答 | 212点数解答 | 2026-01-05 12:17:36]