【HDOJ】3732 Ahui Writes Word

初看01背包，果断TLE。是因为n和C都比较大。但是vi和ci却很小，转化为多重背包。

 #include <cstdio>
 #include <cstring>

 int map[][];
 int dp[];
 int n, C;

 int max(int a, int b) {
     return a>b ? a:b;
 }

 void ZeroOnePack(int v, int c) {
     for (int i=C; i>=c; --i)
         dp[i] = max(dp[i-c]+v, dp[i]);
 }

 void CompeletePack(int v, int c) {
     for (int i=c; i<=C; ++i)
         dp[i] = max(dp[i-c]+v, dp[i]);
 }

 void MultiPack(int v, int c, int k) {
     if (c*k >= C) {
         CompeletePack(v, c);
         return ;
     }
     int r = ;
     while (r < k) {
         ZeroOnePack(r*v, r*c);
         k = k - r;
         r <<= ;
     }
     ZeroOnePack(k*v, k*c);
 }

 int main() {
     int v, c;
     char s[];
     int i, j;

     while (scanf("%d %d", &n, &C) != EOF) {
         memset(map, , sizeof(map));
         memset(dp, , sizeof(dp));
         for (i=; i<n; ++i) {
             scanf("%s %d %d", s, &v, &c);
             map[v][c]++;
         }
         for (i=; i<=; ++i) {
             for (j=; j<=; ++j) {
                 if (map[i][j])
                     MultiPack(i, j, map[i][j]);
             }
         }
         printf("%d\n", dp[C]);
     }

     return ;
 }