#include <bits/stdc++.h> // author : aykhn using namespace std; typedef long long ll; #define pb push_back #define ins insert #define mpr make_pair #define all(v) v.begin(), v.end() #define bpc __builtin_popcount #define pii pair<int, int> #define pll pair<ll, ll> #define fi first #define se second #define int ll #define infll 0x3F3F3F3F3F3F3F3F #define inf 0x3F3F3F3F const int MXN = 55; int n, m; int dp[MXN][MXN][MXN][MXN]; int pref[MXN][MXN]; int a[MXN][MXN]; int sum(int i1, int j1, int i2, int j2) { int x = pref[i1 - 1][j2]; int y = pref[i2][j1 - 1]; return pref[i2][j2] - x - y + pref[i1 - 1][j1 - 1]; } int f(int i1, int j1, int i2, int j2) { if (i1 == i2 && j1 == j2) return 0; if (dp[i1][j1][i2][j2] != -1) return dp[i1][j1][i2][j2]; int res = inf; int id = -1; for (int k = j1; k < j2; k++) { int x = f(i1, j1, i2, k) + f(i1, k + 1, i2, j2); if (x < res) { id = k; res = x; } } for (int k = i1; k < i2; k++) { int x = f(i1, j1, k, j2) + f(k + 1, j1, i2, j2); if (x < res) { id = -k; res = x; } } return dp[i1][j1][i2][j2] = res + sum(i1, j1, i2, j2); } void _() { cin >> n >> m; for (int i = 1; i <= n; i++) { for (int j = 1; j <= m; j++) { cin >> a[i][j]; for (int k = 1; k <= n; k++) { for (int l = 1; l <= m; l++) { dp[i][j][k][l] = -1; } } } } for (int i = 1; i <= n; i++) { for (int j = 1; j <= m; j++) { pref[i][j] = pref[i - 1][j] + pref[i][j - 1] - pref[i - 1][j - 1] + a[i][j]; } } cout << f(1, 1, n, m) << '\n'; } signed main() { ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); int t = 1; //cin >> t; for (int i = 1; i <= t; i++) { _(); } }

raisins.cpp: In function 'll f(ll, ll, ll, ll)':
raisins.cpp:40:9: warning: variable 'id' set but not used [-Wunused-but-set-variable]
   40 |     int id = -1;
      |         ^~