CodeForces 225B Well-known Numbers（二分）

#include <iostream>#include <vector>using namespace std;//求出所有不大于s的k-bonacci数，放到 f 中，然后每次贪最接近s的数，放入 ans 中vector<int>f;vector<int>ans;int binary_search(int target){int low = 1, high = f.size() - 1, mid;while (low + 1 < high){mid = (low + high) / 2;if (f[mid] >= target)high = mid - 1;else low = mid;}if (f[high] < target)return high;return low;}int main(){int s, k;cin >> s >> k;f.push_back(0);f.push_back(1);int sum = 1;f.push_back(sum);while (sum < s){int tmp = 0;if ((int)f.size() - 1 - k > 0)tmp = f[f.size() - 1 - k];sum = sum * 2 - tmp;f.push_back(sum);}int num = s;while (num>0){int index = binary_search(num);if (f[index + 1] == num){ans.push_back(f[index + 1]);num = 0;}else{ans.push_back(f[index]);num -= f[index];}}ans.push_back(0);cout << ans.size() << endl;cout << ans[0];for (int i = 1; i < ans.size(); i++)cout << ' ' << ans[i];cout << endl;return 0;}