This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
#define endl "\n"
#define see(x) cerr<<#x<<"="<<x<<endl;
using namespace std;
const int N = 1002;
int m, n, val[N*N], ans, k, cnt;
bool spec[N*N], used[N*N];
vector <int> g[N*N], values;
void dfs (int v) {
	used[v] = true;
	if (spec[v]) ++ cnt;
	else values.push_back(val[v]);
	for (auto i: g[v])
		if (!used[i]) dfs(i);
}
int32_t main () {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    cin >> m >> n;
    int temp = 1;
    for (int i = 0; i < m; ++ i)
    	for (int j = 0; j < n; ++ j) {
    		int a; cin >> a;
    		val[temp ++] = a;
    	}
   	cin >> k;
   	for (int i = 0; i < k; ++ i) {
   		int x, y;
   		cin >> x >> y;
   		++ x; ++ y;
   		int t = (x-1)*n + y,
   		t1 = (x-2)*n + y,
   		t2 = (x-1)*n + y - 1,
   		t3 = x*n + y,
   		t4 = (x-1)*n + y + 1;
   		ans += val[t];
   		spec[t] = true;
   		if (x > 1) {
   			g[t].push_back(t1);
   			g[t1].push_back(t);
   		}
   		if (y > 1) {
   			g[t].push_back(t2);
   			g[t2].push_back(t);
   		}
   		if (x < m) {
   			g[t].push_back(t3);
   			g[t3].push_back(t);
   		}
   		if (y < n) {
   			g[t].push_back(t4);
   			g[t4].push_back(t);
   		}
   	}
   	temp = 1;
   	for (int i = 0; i < m; ++ i)
   		for (int j = 0; j < n; ++ j) {
   			if (!used[temp]) {
   				values.clear();
   				cnt = 0;
   				dfs(temp);
   				sort(values.rbegin(), values.rend());
   				if (3*cnt > values.size()) {
   					cout << "No\n";
   					return 0;
   				}
   				for (int k = 0; k < 3*cnt; ++ k)
   					ans += values[k];
   			}
   			++ temp;
   		}
   	cout << ans << endl;
    return 0;
}
Compilation message (stderr)
covering.cpp: In function 'int32_t main()':
covering.cpp:29:5: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
     for (int i = 0; i < m; ++ i)
     ^~~
covering.cpp:35:5: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
     cin >> k;
     ^~~
covering.cpp:74:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
        if (3*cnt > values.size()) {
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