【每日一题】6月8日[SCOI2005]最大子矩阵
[SCOI2005]最大子矩阵
https://ac.nowcoder.com/acm/problem/20242
多唯DP
Code
#pragma GCC target("avx,sse2,sse3,sse4,popcnt") #pragma GCC optimize("O2,O3,Ofast,inline,unroll-all-loops,-ffast-math") #include <bits/stdc++.h> using namespace std; #define js ios::sync_with_stdio(false);cin.tie(0); cout.tie(0) #define all(vv) vv.begin(), vv.end() #define endl "\n" typedef long long ll; typedef unsigned long long ull; typedef long double ld; const ll MOD = 1e9 + 7; inline ll read() { ll s = 0, w = 1; char ch = getchar(); for (; !isdigit(ch); ch = getchar()) if (ch == '-') w = -1; for (; isdigit(ch); ch = getchar()) s = (s << 1) + (s << 3) + (ch ^ 48); return s * w; } inline void write(ll x) { if (!x) { putchar('0'); return; } char F[40]; ll tmp = x > 0 ? x : -x; if (x < 0)putchar('-'); int cnt = 0; while (tmp > 0) { F[cnt++] = tmp % 10 + '0'; tmp /= 10; } while (cnt > 0)putchar(F[--cnt]); } inline ll gcd(ll x, ll y) { return y ? gcd(y, x % y) : x; } ll qpow(ll a, ll b) { ll ans = 1; while (b) { if (b & 1) ans *= a; b >>= 1; a *= a; } return ans; } ll qpow(ll a, ll b, ll mod) { ll ans = 1; while (b) { if (b & 1)(ans *= a) %= mod; b >>= 1; (a *= a) %= mod; }return ans % mod; } inline int lowbit(int x) { return x & (-x); } const int N = 100 + 7; int s[N][3], dp[N][N][11]; int main() { int n = read(), m = read(), k = read(); for (int i = 1; i <= n; ++i) for (int j = 1; j <= m; ++j) s[i][j] = s[i - 1][j] + read(); for (int i = 1; i <= n; ++i) // 第一列的末尾选取 for (int j = 1; j <= n; ++j) //第二列 for (int a = 1; a <= k; ++a) { //矩阵个数 dp[i][j][a] = max(dp[i - 1][j][a], dp[i][j - 1][a]); for (int b = 0; b < i; ++b) //第一列状态转移 dp[i][j][a] = max(dp[i][j][a], dp[b][j][a - 1] + s[i][1] - s[b][1]); for (int b = 0; b < i; ++b) //第二列状态转移 dp[i][j][a] = max(dp[i][j][a], dp[i][b][a - 1] + s[j][2] - s[b][2]); if (i == j) for (int b = 0; b < i; ++b) //选底长为2的矩阵转移 dp[i][j][a] = max(dp[i][j][a], dp[b][b][a - 1] + s[i][1] + s[j][2] - s[b][1] - s[b][2]); } write(dp[n][n][k]); return 0; }
每日一题 文章被收录于专栏
每日一题