【HDOJ】4374 One hundred layer

线性DP，使用单调队列优化。

 /* 4374 */
 #include <iostream>
 #include <sstream>
 #include <string>
 #include <map>
 #include <queue>
 #include <set>
 #include <stack>
 #include <vector>
 #include <deque>
 #include <algorithm>
 #include <cstdio>
 #include <cmath>
 #include <ctime>
 #include <cstring>
 #include <climits>
 #include <cctype>
 #include <cassert>
 #include <functional>
 #include <iterator>
 #include <iomanip>
 using namespace std;
 //#pragma comment(linker,"/STACK:102400000,1024000")

 #define sti                set<int>
 #define stpii            set<pair<int, int> >
 #define mpii            map<int,int>
 #define vi                vector<int>
 #define pii                pair<int,int>
 #define vpii            vector<pair<int,int> >
 #define rep(i, a, n)     for (int i=a;i<n;++i)
 #define per(i, a, n)     for (int i=n-1;i>=a;--i)
 #define clr                clear
 #define pb                 push_back
 #define mp                 make_pair
 #define fir                first
 #define sec                second
 #define all(x)             (x).begin(),(x).end()
 #define SZ(x)             ((int)(x).size())
 #define lson            l, mid, rt<<1
 #define rson            mid+1, r, rt<<1|1

 const int INF = 0x3f3f3f3f;
 const int maxn = ;
 const int maxm = ;
 int n, m, x, t;
 int score[maxn][maxm];
 int dp[maxn][maxm];
 int P[maxm], Q[maxm];
 int sum[maxm];

 void solve() {
     int i, j, k;
     int lpos, rpos;
     int l, r, tmp;

     for (i=; i<=n; ++i)
         for (j=; j<=m; ++j)
             dp[i][j] = -INF;

     for (j=; j<=m; ++j)
         sum[j] = sum[j-] + score[][j];
     for (lpos=max(,x-t),j=lpos; j<=x; ++j)
         dp[][j] = sum[x] - sum[j-];
     for (rpos=min(m,x+t),j=rpos; j>x; --j)
         dp[][j] = sum[j] - sum[x-];

     for (i=; i<=n; ++i) {
         for (j=; j<=m; ++j)
             sum[j] = sum[j-] + score[i][j];

         // k <= j
         l = , r =;
         for (j=; j<=m; ++j) {
             lpos = max(, j-t);
             tmp = dp[i-][j] - sum[j-];
             while (l<=r && Q[r]<=tmp)
                 --r;
             Q[++r] = tmp;
             P[r] = j;
             while (P[l] < lpos)
                 ++l;
             dp[i][j] = max(dp[i][j], Q[l] + sum[j]);
         }

         // k>=j
         l = , r =;
         for (j=m; j>=; --j) {
             rpos = min(m, j+t);
             tmp = dp[i-][j] + sum[j];
             while (l<=r && Q[r]<=tmp)
                 --r;
             Q[++r] = tmp;
             P[r] = j;
             while (P[l] > rpos)
                 ++l;
             dp[i][j] = max(dp[i][j], Q[l] - sum[j-]);
         }
     }

     int ans = -INF;

     rep(j, , m+)
         ans = max(ans, dp[n][j]);

     printf("%d\n", ans);
 }

 int main() {
     ios::sync_with_stdio(false);
     #ifndef ONLINE_JUDGE
         freopen("data.in", "r", stdin);
         freopen("data.out", "w", stdout);
     #endif

     while (scanf("%d %d %d %d", &n, &m, &x, &t)!=EOF) {
         rep(i, , n+)
             rep(j, , m+)
                 scanf("%d", &score[i][j]);
         solve();
     }

     #ifndef ONLINE_JUDGE
         printf("time = %d.\n", (int)clock());
     #endif

     return ;
 }

数据发生器。

 from copy import deepcopy
 from random import randint, shuffle
 import shutil
 import string

 def GenDataIn():
     with open("data.in", "w") as fout:
         t = 10
         bound = 10**5
         # fout.write("%d\n" % (t))
         for tt in xrange(t):
             n = randint(1, 100)
             m = randint(1, 10000)
             x = randint(1, m)
             t = randint(1, m)
             fout.write("%d %d %d %d\n" % (n, m, x, t))
             for i in xrange(n):
                 L = []
                 for j in xrange(m):
                     x = randint(-500, 500)
                     L.append(x)
                 fout.write(" ".join(map(str, L)) + "\n")

 def MovDataIn():
     desFileName = "F:\eclipse_prj\workspace\hdoj\data.in"
     shutil.copyfile("data.in", desFileName)

 if __name__ == "__main__":
     GenDataIn()
     MovDataIn()