区间dp题汇

 1 #include <bits/stdc++.h>
 2 using namespace std;
 3 #define rep(i, a, b) for (int i = a; i <= b; ++i)
 4 const int N = 57;
 5 
 6 int n, f[N][N]; char a[N];
 7 
 8 int main() {
 9     scanf("%s", a + 1); n = strlen(a + 1); memset(f, 0x3f, sizeof(f)); 
10     rep(i, 1, n) {
11         f[i][i] = 1;
12     }
13     
14     rep(len, 2, n) rep(i, 1, n - len + 1) { int j = i + len - 1;
15         rep(k, i, j - 1) {
16             if (a[i] == a[j]) f[i][j] = min(f[i][j], f[i][k] + f[k + 1][j] - 1);
17             else f[i][j] = min(f[i][j], f[i][k] + f[k + 1][j]);
18         }
19     }
20     
21     printf("%d\n", f[1][n]);
22     return 0;
23 }

 1 #include <bits/stdc++.h>
 2 using namespace std;
 3 #define rep(i, a, b) for (int i = a; i <= b; ++i)
 4 const int N = 207;
 5 
 6 int n, a[N], f[N][N], ans;
 7 
 8 int main() {
 9     scanf("%d", &n);
10     rep(i, 1, n) {
11         scanf("%d", &a[i]);
12         a[n + i] = a[i];
13     }
14     
15     rep(len, 2, n + 1) rep(i, 1, n * 2 - len + 1) { int j = i + len - 1; 
16         rep(k, i + 1, j - 1) {
17             f[i][j] = max(f[i][j], f[i][k] + f[k][j] + a[i] * a[k] * a[j]);
18         }
19 //        cout << i << ‘ ‘ << j << ‘ ‘ << f[i][j] << ‘\n‘;
20         if (len == n + 1) ans = max(ans, f[i][j]);
21     }
22     
23     printf("%d\n", ans);
24     return 0;
25 }

 1 #include <bits/stdc++.h>
 2 using namespace std;
 3 typedef long long ll;
 4 #define rep(i, a, b) for (ll i = a; i <= b; ++i)
 5 const ll N = 87;
 6 
 7 ll n, m, a[N], f[N][N], ans;
 8 
 9 int main() {
10     scanf("%lld%lld", &n, &m);
11     
12     while (n--) {
13         memset(f, 0, sizeof(f));
14         rep(i, 1, m) {
15             scanf("%lld", &a[i]);
16             f[i][i] = a[i] * (1 << m);
17         }
18         rep(len, 2, m) rep(i, 1, m - len + 1) { ll j = i + len - 1;
19             f[i][j] = max(f[i][j], max(f[i][j - 1] + a[j] * (1 << (m + 1 - len)), f[i + 1][j] + a[i] * (1 << (m + 1 - len))));
20         }
21         ans += f[1][m];
22     }
23     printf("%lld\n", ans);
24     return 0;
25 }

 1 #include <bits/stdc++.h>
 2 using namespace std;
 3 #define rep(i, a, b) for (int i = a; i <= b; ++i)
 4 
 5 const int N = 57;
 6 
 7 int n, c, p[N], v[N], s[N], f[N][N][2];
 8 
 9 inline int cal(int x, int y, int l, int r) {
10     return (p[y] - p[x]) * (s[n] - s[r] + s[l - 1]);
11 }
12 
13 int main() {
14     scanf("%d%d", &n, &c);
15 
16     memset(f, 0x3f, sizeof(f));
17     f[c][c][0] = f[c][c][1] = 0;
18 
19     rep(i, 1, n) {
20         scanf("%d%d", &p[i], &v[i]);
21         s[i] = s[i - 1] + v[i];
22     }
23 
24     rep(l, 2, n) rep(i, 1, n - l + 1) {
25         int j = i + l - 1;
26         f[i][j][0] = min(f[i + 1][j][0] + cal(i, i + 1, i + 1, j), f[i + 1][j][1] + cal(i, j, i + 1, j));
27         f[i][j][1] = min(f[i][j - 1][0] + cal(i, j, i, j - 1), f[i][j - 1][1] + cal(j - 1, j, i, j - 1));
28     }
29 
30     printf("%d\n", min(f[1][n][0], f[1][n][1]));
31 
32     return 0;
33 }