Codeforces Round #FF (Div. 1) B. DZY Loves Modification

枚举行取了多少次，如行取了i次，列就取了k-i次，假设行列单独贪心考虑然后相加，那么有i*(k-i)个交点是多出来的：dpr[i]+dpc[k-i]-i*(k-i)*p

枚举i取最大值。。。。

B. DZY Loves Modification

time limit per test
2 seconds

memory limit per test
256 megabytes

input
standard input

output
standard output

As we know, DZY loves playing games. One day DZY decided to play with a n × m matrix. To be more precise, he decided to modify the matrix with exactly k operations.

Each modification is one of the following:

Pick some row of the matrix and decrease each element of the row by p. This operation brings to DZY the value of pleasure equal to the sum of elements of
the row before the decreasing.

Pick some column of the matrix and decrease each element of the column by p. This operation brings to DZY the value of pleasure equal to the sum of elements
of the column before the decreasing.

DZY wants to know: what is the largest total value of pleasure he could get after performing exactly k modifications? Please, help him to calculate this
value.

Input

The first line contains four space-separated integers n, m, k and p (1 ≤ n, m ≤ 103; 1 ≤ k ≤ 106; 1 ≤ p ≤ 100).

Then n lines follow. Each of them contains m integers
representing aij (1 ≤ aij ≤ 103) —
the elements of the current row of the matrix.

Output

Output a single integer — the maximum possible total pleasure value DZY could get.

Sample test(s)

input

2 2 2 2
1 3
2 4

output

11

input

2 2 5 2
1 3
2 4

output

11

Note

For the first sample test, we can modify: column 2, row 2. After that the matrix becomes:

1 1
0 0

For the second sample test, we can modify: column 2, row 2, row 1, column 1, column 2. After that the matrix becomes:

-3 -3
-2 -2

#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <queue>

using namespace std;

typedef long long int LL;

const int maxn=1100;

LL dpr[maxn*maxn],dpc[maxn*maxn];
LL col[maxn],row[maxn];
LL a[maxn][maxn];
priority_queue<LL> qc,qr;
int n,m,k; LL p;

int main()
{
scanf("%d%d%d%I64d",&n,&m,&k,&p);
for(int i=0;i<n;i++)
{
for(int j=0;j<m;j++)
{
scanf("%I64d",&a[i][j]);
col[j]+=a[i][j];
row[i]+=a[i][j];
}
}
for(int i=0;i<n;i++)
qr.push(row[i]);
for(int i=0;i<m;i++)
qc.push(col[i]);
dpr[0]=dpc[0]=0;
for(int i=1;i<=k;i++)
{
LL cc=qc.top(); qc.pop();
LL rr=qr.top(); qr.pop();
dpr[i]=dpr[i-1]+rr;
dpc[i]=dpc[i-1]+cc;
qc.push(cc-p*n);
qr.push(rr-p*m);
}
LL ans=dpr[0]+dpc[k];
for(int i=1;i<=k;i++)
ans=max(ans,dpr[i]+dpc[k-i]-1LL*i*(k-i)*p);
printf("%I64d",ans);
return 0;
}