// 1319. Number of Operations to Make Network Connected #include #include #include int union_find(int *u, int val) { if (u[val] == val) return val; return union_find(u, u[val]); } bool union_set(int *u, int *usize, int a, int b) { int find_a = union_find(u, a); int find_b = union_find(u, b); if (find_a == find_b) return false; if (usize[find_a] > usize[find_b]) { u[find_b] = u[find_a]; usize[find_a] += usize[find_b]; } else { u[find_a] = u[find_b]; usize[find_b] += usize[find_a]; } return true; } int makeConnected(int n, int **connections, int connections_size, int *connections_col_size) { if (connections_size < n - 1) return -1; int *u = malloc(n * sizeof(int)); int *usize = malloc(n * sizeof(int)); for (int i = 0; i < n; i++) { u[i] = i; usize[i] = 1; } int ans = 0; for (int i = 0; i < connections_size; i++) if (union_set(u, usize, connections[i][0], connections[i][1]) == false) ans++; if (connections_size - ans >= n - 1) return 0; else return (n - 1) - (connections_size - ans); } int main() { int c1[3][2] = {{0, 1}, {0, 2}, {1, 2}}; int c2[5][2] = {{0, 1}, {0, 2}, {0, 3}, {1, 2}, {1, 3}}; int c3[5][2] = {{0, 1}, {0, 2}, {0, 3}, {1, 2}, {1, 3}}; int c1_c_s[] = {3}, c2_c_s[] = {5}, c3_c_s[] = {5}; printf("%d\n", makeConnected(4, c1, 3, c1_c_s)); printf("%d\n", makeConnected(6, c2, 5, c1_c_s)); printf("%d\n", makeConnected(6, c3, 5, c1_c_s)); }