#include <cstdio> #include <vector> int n, b, r; bool matrix[4][256][256]; std::vector<int> robots; bool Check(int number) { for (int robot : robots) { for (int i = b + 1; i <= n; i++) { if (matrix[number][robot][i]) { return false; } } } return true; } void Multiply(int a, int b, int c) { for (int i = 1; i <= n; i++) { for (int j = 1; j <= n; j++) { matrix[c][i][j] = false; } } for (int i = 1; i <= n; i++) { for (int k = 1; k <= n; k++) { for (int j = 1; j <= n; j++) { matrix[c][i][j] = matrix[c][i][j] or (matrix[a][i][k] and matrix[b][k][j]); } } } } int main() { scanf("%d%d%d", &n, &b, &r); for (int i = 1; i <= n; i++) { matrix[0][i][i] = true; } for (int i = 1; i <= n; i++) { for (int j = 1; j <= n; j++) { char c; scanf(" %c", &c); matrix[1][i][j] = (c == '1'); } } for (int i = 0; i < r; i++) { int a; scanf("%d", &a); robots.push_back(a); } const int max_computation = (100 * 1000 * 1000) / (n * n * n); if (Check(1)) { printf("%d\n", 0); return 0; } for (int i = 1; i < max_computation; i++) { Multiply((i + 3) % 4, i % 4, (i + 1) % 4); if (Check((i + 1) % 4)) { printf("%d\n", i); return 0; } } printf("-1\n"); 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 | #include <cstdio> #include <vector> int n, b, r; bool matrix[4][256][256]; std::vector<int> robots; bool Check(int number) { for (int robot : robots) { for (int i = b + 1; i <= n; i++) { if (matrix[number][robot][i]) { return false; } } } return true; } void Multiply(int a, int b, int c) { for (int i = 1; i <= n; i++) { for (int j = 1; j <= n; j++) { matrix[c][i][j] = false; } } for (int i = 1; i <= n; i++) { for (int k = 1; k <= n; k++) { for (int j = 1; j <= n; j++) { matrix[c][i][j] = matrix[c][i][j] or (matrix[a][i][k] and matrix[b][k][j]); } } } } int main() { scanf("%d%d%d", &n, &b, &r); for (int i = 1; i <= n; i++) { matrix[0][i][i] = true; } for (int i = 1; i <= n; i++) { for (int j = 1; j <= n; j++) { char c; scanf(" %c", &c); matrix[1][i][j] = (c == '1'); } } for (int i = 0; i < r; i++) { int a; scanf("%d", &a); robots.push_back(a); } const int max_computation = (100 * 1000 * 1000) / (n * n * n); if (Check(1)) { printf("%d\n", 0); return 0; } for (int i = 1; i < max_computation; i++) { Multiply((i + 3) % 4, i % 4, (i + 1) % 4); if (Check((i + 1) % 4)) { printf("%d\n", i); return 0; } } printf("-1\n"); return 0; } |