Solved! Difficulty: Div2B-Div2C 思考题 that seems easy A perfect word Given N strings. Find out a longest string so that each substring of it is one of the N strings. Example Input str={a,t,at,orange} Output at Constriants Subtask 1(30%):N<……

Solved! Difficulty: D2E 思考题 for everyone Man on Graph You are given M chains each of N+1 nodes. We call the i-th node on the j-th chain (j,i-1). We define a bridge edge connecting (a,b) and (c,d) as follows: - a≠c - b=d - b and d don't equ……

Solved! Difficulty: Div2E 思考题for everyone Dynamic DP You are given: integer arrays A and dp of length N. integer arrays l and r of length N. For each 2\leq i\leq N,1\leq l_i\leq r_i\leq i-1 Known: dp_1=A_1 dp_i=min(dp[l_i,r_i])+A_i for 2\l……