Problem: K: Relief (Angel Relief)

Tenma, an angel, decides to save a city.

The city has a rectangular shape divided into north-south $ H $ parcels x east-west $ W $ parcels, with houses in each parcel.

The $ X $ th section from the north and the $ Y $ th section from the west are represented by $ (X, Y) $.

The house in parcel $ (i, j) $ is inhabited by $ A_ {i, j} $ people.

Tenshin chooses a rectangular area whose sides are parallel or vertical to north-south or east-west, and rescues all the people living in it one by one.

Tenshin does this for every possible rectangle.

Find the total number of times Tenma-san rescues people.

input

The integers $ H, W $ are given on the first line, separated by blanks.

Of the following $ H $ lines, the integers $ A_ {i, 1}, A_ {i, 2}, A_ {i, 3}, \ dots, A_ {i, W} $ are blank on the $ i $ line. Given as a delimiter.

output

Output the total number of times Tenma-san rescues people.

Constraint

* $ H, W $ are integers between $ 1 $ and $ 500 $
* $ A_ {i, j} $ are all integers greater than or equal to $ 1 $ and less than or equal to $ 9 $.



Input example 1


twenty two
1 2
4 8


Output example 1


60


For example, if you choose a rectangular area with $ (1, 1) $ in the upper left and $ (2, 2) $ in the lower right, you will rescue $ 15 $ people there one by one, so a total of $ 15 $ times. Relief.

$ 1, 2, 3, 4, 5, 8, 10, 12, 15 $ relief for each of the $ 9 $ rectangular areas, for a total of $ 60 $.

Input example 2


twenty three
one two Three
4 5 6


Output example 2


140






Example

Input

2 2
1 2
4 8


Output

60

Solution (in CPP):

Solution:
#include<bits/stdc++.h>
using namespace std;
#define lp(i,n) for(int i=0;i<n;i++)
#define lps(i,j,n) for(int i=j;i<n;i++)
#define fordebug int hoge;cin>>hoge;
#define DEKAI 1000000007;
#define INF (1<<28)
#define int long long
#define double long double
#define floot10 cout<<fixed<<setprecision(10)
int ans[500],anss[500];

signed main(){
  int h,w;
  cin>>h>>w;
  int now=1;
  int mode=0;
  int s;
  lp(i,(h+1)/2){
    s=i+1;
    now=0;
    mode=0;
    lp(j,h){
      if(now<s&&mode==0) now++;
      if(mode==1) now--;
      ans[j]+=now;
      if(h-s==j) mode=1;
    }
  }
  if(h%2==0){
    s++;
  }
  while(1){
    s--;
    if(s==0) break;
    now=0;
    mode=0;
    lp(j,h){
      if(now<s&&mode==0) now++;
      if(mode==1) now--;
      ans[j]+=now;
      if(h-s==j) mode=1;
    }
  }
  lp(i,(w+1)/2){
    s=i+1;
    now=0;
    mode=0;
    lp(j,w){
      if(now<s&&mode==0) now++;
      if(mode==1) now--;
      anss[j]+=now;
      if(w-s==j) mode=1;
    }
  }
  if(w%2==0){
    s++;
  }
  while(1){
    s--;
    if(s==0) break;
    now=0;
    mode=0;
    lp(j,w){
      if(now<s&&mode==0) now++;
      if(mode==1) now--;
      anss[j]+=now;
      if(w-s==j) mode=1;
    }
  }
  /*lp(i,h){
    cout<<ans[i];
  }
  cout<<endl;
  lp(j,w)cout<<anss[j];
  cout<<endl;*/
  int cn=0;
  lp(i,h){
    lp(j,w){
      int n;
      cin>>n;
      cn+=n*(ans[i]*anss[j]);
    }
  }
  cout<<cn<<endl;
  return 0;
}