Assign Workers to Jobs

**Tình huống.** n ≤ 500 workers, n ≤ 500 jobs; worker i can do job j iff edge (i, j) exists. Maximize the number of filled jobs. **Thuật toán nào phù hợp nhất? Chương trình chỉ cần in ra chữ cái.** **A)** Greedy: everyone takes their first available job **B)** Kruskal spanning tree on workers **C)** Bipartite matching with augmenting paths (Kuhn / Hopcroft-Karp) **D)** Prefix sums over workers