#include <bits/stdc++.h>
using namespace std;
const int MN=3001;
int pfs[MN][MN], q[MN][MN];
int qry(int r1, int c1, int r2, int c2) {
int ans = pfs[r2][c2];
if(r1 > 0) ans -= pfs[r1-1][c2];
if(c1 > 0) ans -= pfs[r2][c1-1];
if(r1 > 0 && c1 > 0) ans += pfs[r1-1][c1-1];
return ans;
}
int rectangle(int R, int C, int H, int W, int Q[MN][MN]) {
int l = 1, h = R*C, target = H*W/2, ans;
while(l <= h) {
int X = (l+h)/2;
bool chk = 0;
for(int r=0; r<R; ++r) {
for(int c=0; c<C; ++c) {
pfs[r][c] = Q[r][c] <= X;
if(r > 0) pfs[r][c] += pfs[r-1][c];
if(c > 0) pfs[r][c] += pfs[r][c-1];
if(r > 0 && c > 0) pfs[r][c] -= pfs[r-1][c-1];
}
}
for(int r=0; r+H-1<R; ++r) {
for(int c=0; c+W-1<C; ++c) {
if(qry(r, c, r+H-1, c+W-1) > target) {
chk = 1;
}
}
}
if(chk) {
h = X-1;
ans = X;
} else l = X+1;
}
return ans;
}
int main() {
ios::sync_with_stdio(0);cin.tie(0);
int R,C,H,W;
cin>>R>>C>>H>>W;
for(int r=0; r<R; ++r) {
for(int c=0; c<C; ++c) cin>>q[r][c];
}
cout<<rectangle(R,C,H,W,q)<<'\n';
return 0;
}
Compilation message
quality.cpp: In function 'int rectangle(int, int, int, int, int (*)[3001])':
quality.cpp:43:10: warning: 'ans' may be used uninitialized in this function [-Wmaybe-uninitialized]
43 | return ans;
| ^~~
/usr/bin/ld: /tmp/cc3SOSGm.o: in function `main':
grader.cpp:(.text.startup+0x0): multiple definition of `main'; /tmp/ccaBK2io.o:quality.cpp:(.text.startup+0x0): first defined here
collect2: error: ld returned 1 exit status