#include <bits/stdc++.h> #define ff first #define ss second using namespace std; struct val { int len, spec; }; int t, n; vector<val> tab; bool cmp(val a, val b) { return a.len > b.len; } int main() { scanf("%d", &t); char c; int las, len, z, wyn; bool q; while (t--) { scanf("%d", &n); tab.clear(); q = 0; scanf(" %c", &c); if (c == '0') q = 1; las = c - '0'; len = (c == '0'); for (int i = 1; i < n; i++) { scanf(" %c", &c); if (c == '0') { len++; las = 0; } else { if (las == 0) { tab.push_back({len, 0}); len = 0; } las = 1; } } if (las == 0) tab.push_back({len * 2, 1}); if (q) { if (tab[0].spec) { printf("0\n"); continue; } tab[0].len *= 2; tab[0].spec = 1; } sort(tab.begin(), tab.end(), cmp); // Algorytm zachłanny z = 0; wyn = 0; for (auto i : tab) { i.len -= 2*z; if (i.len <= 0) break; if (i.spec) { wyn += i.len / 2; z++; } else if (i.len == 2 || i.len == 1) { wyn += 1; z++; } else { wyn += i.len - 1; z += 2; } } printf("%d\n", n - wyn); } return 0; }
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 | #include <bits/stdc++.h> #define ff first #define ss second using namespace std; struct val { int len, spec; }; int t, n; vector<val> tab; bool cmp(val a, val b) { return a.len > b.len; } int main() { scanf("%d", &t); char c; int las, len, z, wyn; bool q; while (t--) { scanf("%d", &n); tab.clear(); q = 0; scanf(" %c", &c); if (c == '0') q = 1; las = c - '0'; len = (c == '0'); for (int i = 1; i < n; i++) { scanf(" %c", &c); if (c == '0') { len++; las = 0; } else { if (las == 0) { tab.push_back({len, 0}); len = 0; } las = 1; } } if (las == 0) tab.push_back({len * 2, 1}); if (q) { if (tab[0].spec) { printf("0\n"); continue; } tab[0].len *= 2; tab[0].spec = 1; } sort(tab.begin(), tab.end(), cmp); // Algorytm zachłanny z = 0; wyn = 0; for (auto i : tab) { i.len -= 2*z; if (i.len <= 0) break; if (i.spec) { wyn += i.len / 2; z++; } else if (i.len == 2 || i.len == 1) { wyn += 1; z++; } else { wyn += i.len - 1; z += 2; } } printf("%d\n", n - wyn); } return 0; } |