Stupid Tower Defense

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• Test instructions
  n 1*1 in the horizontal direction, each lattice can grow a plant, passing a lattice time is t. Altogether three kinds of plants: R plants. R point damage received per second after passing, G plant, G-point damage per second after passing, b plant, after passing through a lattice time plus B
  2<=n<=1500,0<=r, G, b<=60000,1<=t<=3
  
• Analysis:
  The most beginning to consider the greedy: first b plants, after g plants, finally B plants. Later found to be wrong.
  First, it is clear that r plants have no effect on the location of the answer, whereas B and G plants grow better early, so the problem lies in the methods of B and G.

  
  The status is expressed to be clear, regardless of the position of G and B. The subsequent situation is only related to the number of B and G. So can DP. DP[I][J] indicates that the total damage of the plant is now a b plant, J G. can be greedy. Implementation of one-dimensional DP processing

LL N, G, B, r, T;    LL Dp[maxn];int Main () {int T;    RI (T);        FE (Kase, 1, T) {cin >> n >> R >> G >> b >> T;        LL ans = n * r * t; CLR (DP,-1);        Dp[0] = 0; REP (all, N) {FED (i, n, 0) {if (~dp[i]) {L                    L NXT = Dp[i] + (i * b + t) * (all-i) * g;                    if (Dp[i + 1] < NXT) Dp[i + 1] = NXT;                    NXT = Dp[i] + (i * b + t) * (all-i) * g;                if (Dp[i] < NXT) Dp[i] = NXT;  }} FE (i, 0, N) {if (~dp[i]) {LL NXT =                    Dp[i] + (N-ALL-1) * (t + i * b) * (R + (all + 1-i) * g);                if (ans < nxt) ans = nxt;    }}} printf ("Case #%d:%i64d\n", Kase, ans); } return 0;}

Stupid Tower Defense