#include <cstdio> #include <cstring> #include <cmath> #include <cassert> #include <iostream> #include <algorithm> #include <iterator> #include <string> #include <vector> #include <queue> #include <bitset> #include <utility> #include <stack> using namespace std; typedef long long LL; typedef pair<int,int> PII; typedef vector<int> VI; #define MP make_pair #define FOR(v,p,k) for(int v=(p);v<=(k);++v) #define FORD(v,p,k) for(int v=(p);v>=(k);--v) #define REP(i,n) for(int i=0;i<(n);++i) #define VAR(v,i) __typeof(i) v=(i) #define FOREACH(i,c) for(VAR(i,(c).begin());i!=(c).end();++i) #define PB push_back #define ST first #define ND second #define SIZE(x) (int)x.size() #define ALL(c) c.begin(),c.end() #define ODD(x) ((x)%2) #define EVEN(x) (!(ODD(x))) VI d, h2, h1; int main() { d.reserve(100009); h2.reserve(100009); h1.reserve(100009); int t; scanf("%d\n", &t); while(t--) { d.clear(); h2.clear(); h1.clear(); int n; scanf("%d\n", &n); REP(i, n) { char c; scanf("%c", &c); d.PB(c-'0'); } int ones = 0; REP(i,n) { ones += (d[i] == 1); } if (ones == 0) { printf("0\n"); continue; } int curr0 = 0; REP(i,n) { if (d[i] == 0) { curr0++; } else { if (curr0 > 0) { if ((h2.size() == 0) && (d[0] == 0) && (h1.size() == 0)) { h1.PB(curr0); } else { h2.PB(curr0); } } curr0 = 0; } } if (curr0 > 0) { h1.PB(curr0); } sort(ALL(h1)); //FOREACH(it, h1) printf("h1: %d\n", *it); sort(ALL(h2)); //FOREACH(it, h2) printf("h2: %d\n", *it); int epochs = 0; while ((h1.size() + h2.size()) > 0) { if ((h1.size() > 0) && (h1.back() - epochs <= 0)) { ones += h1.back(); h1.pop_back(); continue; } if ((h1.size() == 2) && (h1[0] - epochs <= 1)) { swap(h1[0], h1[1]); ones += h1.back(); h1.pop_back(); continue; } if ((h2.size() > 0) && (h2.back() - 2 * epochs <= 0)) { ones += h2.back(); h2.pop_back(); continue; } bool h1_once = false; bool h2_once = false; if (h2.empty()) { h1_once = true; } else if (h1.empty()) { h2_once = true; } else { int b2 = h2.back() - 2 * epochs; int b2_gain = (b2 == 1) ? 1 : b2-1; int b1_gain = h1.back() - epochs; int b1_0_gain = 0; if (h1.size() == 2) { b1_0_gain = h1[0] - epochs - 1; } if (b2_gain > b1_gain + b1_0_gain) { h2_once = true; } else { h1_once = true; } } //if ((h2.empty()) || ((h1.size() > 0) && ((h2.back() - 2 * epochs) <= 3) && (h1.back() - epochs > 0))) { if (h1_once) { ones += epochs; epochs++; h1.pop_back(); continue; } //if (h2.size() > 0) { if (h2_once) { int b = h2.back(); int curr = b - 2 * epochs; if (curr == 1) { ones += 2 * epochs; epochs++; } else { ones += 2 * epochs + 1; epochs += 2; } h2.pop_back(); continue; } //assert(0); } printf("%d\n", ones); } 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 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 | #include <cstdio> #include <cstring> #include <cmath> #include <cassert> #include <iostream> #include <algorithm> #include <iterator> #include <string> #include <vector> #include <queue> #include <bitset> #include <utility> #include <stack> using namespace std; typedef long long LL; typedef pair<int,int> PII; typedef vector<int> VI; #define MP make_pair #define FOR(v,p,k) for(int v=(p);v<=(k);++v) #define FORD(v,p,k) for(int v=(p);v>=(k);--v) #define REP(i,n) for(int i=0;i<(n);++i) #define VAR(v,i) __typeof(i) v=(i) #define FOREACH(i,c) for(VAR(i,(c).begin());i!=(c).end();++i) #define PB push_back #define ST first #define ND second #define SIZE(x) (int)x.size() #define ALL(c) c.begin(),c.end() #define ODD(x) ((x)%2) #define EVEN(x) (!(ODD(x))) VI d, h2, h1; int main() { d.reserve(100009); h2.reserve(100009); h1.reserve(100009); int t; scanf("%d\n", &t); while(t--) { d.clear(); h2.clear(); h1.clear(); int n; scanf("%d\n", &n); REP(i, n) { char c; scanf("%c", &c); d.PB(c-'0'); } int ones = 0; REP(i,n) { ones += (d[i] == 1); } if (ones == 0) { printf("0\n"); continue; } int curr0 = 0; REP(i,n) { if (d[i] == 0) { curr0++; } else { if (curr0 > 0) { if ((h2.size() == 0) && (d[0] == 0) && (h1.size() == 0)) { h1.PB(curr0); } else { h2.PB(curr0); } } curr0 = 0; } } if (curr0 > 0) { h1.PB(curr0); } sort(ALL(h1)); //FOREACH(it, h1) printf("h1: %d\n", *it); sort(ALL(h2)); //FOREACH(it, h2) printf("h2: %d\n", *it); int epochs = 0; while ((h1.size() + h2.size()) > 0) { if ((h1.size() > 0) && (h1.back() - epochs <= 0)) { ones += h1.back(); h1.pop_back(); continue; } if ((h1.size() == 2) && (h1[0] - epochs <= 1)) { swap(h1[0], h1[1]); ones += h1.back(); h1.pop_back(); continue; } if ((h2.size() > 0) && (h2.back() - 2 * epochs <= 0)) { ones += h2.back(); h2.pop_back(); continue; } bool h1_once = false; bool h2_once = false; if (h2.empty()) { h1_once = true; } else if (h1.empty()) { h2_once = true; } else { int b2 = h2.back() - 2 * epochs; int b2_gain = (b2 == 1) ? 1 : b2-1; int b1_gain = h1.back() - epochs; int b1_0_gain = 0; if (h1.size() == 2) { b1_0_gain = h1[0] - epochs - 1; } if (b2_gain > b1_gain + b1_0_gain) { h2_once = true; } else { h1_once = true; } } //if ((h2.empty()) || ((h1.size() > 0) && ((h2.back() - 2 * epochs) <= 3) && (h1.back() - epochs > 0))) { if (h1_once) { ones += epochs; epochs++; h1.pop_back(); continue; } //if (h2.size() > 0) { if (h2_once) { int b = h2.back(); int curr = b - 2 * epochs; if (curr == 1) { ones += 2 * epochs; epochs++; } else { ones += 2 * epochs + 1; epochs += 2; } h2.pop_back(); continue; } //assert(0); } printf("%d\n", ones); } return 0; } |