#include <bits/stdc++.h> using namespace std; int n; void solve() { cin >> n; string s; cin >> s; int l = 0; vector<int> v; for (int i = 0; i < n; ++i) { if (s[i] == '1') { if (i != l) v.push_back(i - l); l = i + 1; } } int left = 0, right = 0; if (s.back() == '0') { right = n - l; } if (!v.empty() && s[0] == '0') { left = v[0]; v.erase(v.begin()); } sort(v.begin(), v.end(), greater<int>()); // cout << "V: "; // for (int &i : v) // cout << i << ' '; // cout << '\n'; int sum = 0, time = 0; for (int i = 0; i < v.size();) { if (left - time == 3 && right - time == 3 && v[i] - time == 5) { cout << n - sum - 6 << '\n'; return; } if ((left > time || right > time) && (left >= v[i] - 1 || right >= v[i] - 1)) { if (left > right) { sum += left - time; time += 2; ++right; left = 0; } else { sum += right - time; time += 2; ++left; right = 0; } // cout << "SUM IS NOW: " << sum << '\n'; // cout << "TIME IS NOW: " << time << '\n'; continue; } if (v[i] <= time) break; if (v[i] == time + 1) { ++sum; ++time; // cout << "SUM IS NOW: " << sum << '\n'; // cout << "TIME IS NOW: " << time << '\n'; break; } sum += v[i] - time - 1; time += 4; left += 2; right += 2; // cout << "SUM IS NOW: " << sum << '\n'; // cout << "TIME IS NOW: " << time << '\n'; ++i; } if (left > time) { sum += left - time++; // cout << "SUM IS NOW: " << sum << '\n'; } if (right > time) { sum += right - time; // cout << "SUM IS NOW: " << sum << '\n'; } cout << n - sum << '\n'; } int main() { ios_base::sync_with_stdio(false); cin.tie(nullptr); int z; cin >> z; while (z--) solve(); }
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 | #include <bits/stdc++.h> using namespace std; int n; void solve() { cin >> n; string s; cin >> s; int l = 0; vector<int> v; for (int i = 0; i < n; ++i) { if (s[i] == '1') { if (i != l) v.push_back(i - l); l = i + 1; } } int left = 0, right = 0; if (s.back() == '0') { right = n - l; } if (!v.empty() && s[0] == '0') { left = v[0]; v.erase(v.begin()); } sort(v.begin(), v.end(), greater<int>()); // cout << "V: "; // for (int &i : v) // cout << i << ' '; // cout << '\n'; int sum = 0, time = 0; for (int i = 0; i < v.size();) { if (left - time == 3 && right - time == 3 && v[i] - time == 5) { cout << n - sum - 6 << '\n'; return; } if ((left > time || right > time) && (left >= v[i] - 1 || right >= v[i] - 1)) { if (left > right) { sum += left - time; time += 2; ++right; left = 0; } else { sum += right - time; time += 2; ++left; right = 0; } // cout << "SUM IS NOW: " << sum << '\n'; // cout << "TIME IS NOW: " << time << '\n'; continue; } if (v[i] <= time) break; if (v[i] == time + 1) { ++sum; ++time; // cout << "SUM IS NOW: " << sum << '\n'; // cout << "TIME IS NOW: " << time << '\n'; break; } sum += v[i] - time - 1; time += 4; left += 2; right += 2; // cout << "SUM IS NOW: " << sum << '\n'; // cout << "TIME IS NOW: " << time << '\n'; ++i; } if (left > time) { sum += left - time++; // cout << "SUM IS NOW: " << sum << '\n'; } if (right > time) { sum += right - time; // cout << "SUM IS NOW: " << sum << '\n'; } cout << n - sum << '\n'; } int main() { ios_base::sync_with_stdio(false); cin.tie(nullptr); int z; cin >> z; while (z--) solve(); } |