vijos 1038 括号+路径 ***

链接：点我

就是自己写不出来

 1 #include <cstdio>
 2 #include <climits>
 3 #include <memory.h>
 4 using namespace std;
 5 const int MAX = 23;
 6
 7 int dp[MAX][MAX];
 8 int pos[MAX][MAX];
 9 int val[MAX], sum[MAX][MAX];
10
11 void print_path(int i, int j){
12     if(i == j){
13         printf("%d", val[i]);
14         return;
15     }
16     printf("(");
17     print_path(i, pos[i][j]);
18     printf("+");
19     print_path(pos[i][j] + 1, j);
20     printf(")");
21 }
22
23 int print_intermedia(int x, int y){
24     if(x == y)return val[x];
25     int v = print_intermedia(x, pos[x][y]) + print_intermedia(pos[x][y] + 1, y);
26     printf("%d ", v);
27     return v;
28 }
29
30 int main(int argc, char const *argv[]){
31     int N;
32     scanf("%d", &N);
33     for(int i = 1; i <= N; ++i){
34         scanf("%d", &val[i]);
35     }
36     memset(sum, -1, sizeof(sum));
37
38     for(int i = 1; i <= N; ++i){
39         dp[i][i] = 0;
40         pos[i][i] = i;
41         sum[i][i]= val[i];
42         for(int j = i + 1; j <= N; ++j){
43             sum[i][j] = sum[i][j - 1] + val[j];
44         }
45     }
46
47     for(int j = 1; j < N; ++j){
48         for(int i = 1; i + j <= N; ++i){
49             int opt_v = INT_MAX, opt_p = 0;
50             for(int k = i + j - 1; k >= i; --k){
51                 if(opt_v > dp[i][k] + dp[k + 1][i + j] + sum[i][i + j]){
52                     opt_v = dp[i][k] + dp[k + 1][i + j] + sum[i][i + j];
53                     opt_p = k;
54                 }
55             }
56             pos[i][i + j] = opt_p;
57             dp[i][i + j] = opt_v;
58         }
59     }
60     print_path(1, N);
61     printf("\n");
62     printf("%d\n", dp[1][N]);
63     print_intermedia(1, N);
64     printf("\n");
65
66     return 0;
67 }