Codeforces 463C Gargari and Bishops(贪心)

#include <cstdio>
#include <cstring>
#include <algorithm>

using namespace std;

#define add(a,b) ((a)+(b))
#define del(a,b) ((a)-(b)+2000)

const int maxn = 2005;
typedef long long ll;

int n;
ll g[maxn][maxn], l[maxn*2], r[maxn*2];

int main () {
scanf("%d", &n);
memset(l, 0, sizeof(l));
memset(r, 0, sizeof(r));

for (int i = 1; i <= n; i++)
for (int j = 1; j <= n; j++) {
scanf("%lld\n", &g[i][j]);
l[add(i, j)] += g[i][j];
r[del(i, j)] += g[i][j];
}

int odd_x, odd_y, even_x, even_y;
ll max_odd = -1, max_even = -1;

for (int i = 1; i <= n; i++) {
for (int j = 1; j <= n; j++) {
if ((i+j)&1) {
if (max_odd < l[add(i, j)] + r[del(i, j)] - g[i][j]) {
max_odd = l[add(i, j)] + r[del(i, j)] - g[i][j];
odd_x = i;
odd_y = j;
}
} else {
if (max_even < l[add(i, j)] + r[del(i, j)] - g[i][j]) {
max_even = l[add(i, j)] + r[del(i, j)] - g[i][j];
even_x = i;
even_y = j;
}
}
}
}
printf("%lld\n%d %d %d %d\n", max_even + max_odd, odd_x, odd_y, even_x, even_y);
return 0;
}