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| Hidden Sister (Excel) |
| difficulty level: C; operating time limit: 10 00MS, operating space limit: 256000KB; code length limit: 2000000B |
| question description |
| Today Czy again found three sister, with a collection of hobbies he wants to find three The place hid the girls, and abstracted an empty space into a table of row C of R, Czy to select 3 cells. However, the following two conditions are met:
(1) Any two cells are not in the same row.
(2) Any two cells are not in the same column. The
selection lattice exists for a cost, while this cost is between three lattice 22 and Manhattan distance (e.g. (x1,y1) and (x,y2) of Manhattan Distance for |x1-x2|+|y1-y2|). What the dog wants to know is how many programs it spends between mint and maxt.
Answer modulo 1000000007. The so-called two different scenarios are: As long as the selected cell has a different, it is considered a different scenario. |
| input |
one line, 4 integers, R, C, MinT, Maxt. 3≤r,c≤4000, 1≤mint≤maxt≤20000.
for 30% of data, 3 ≤ r, c ≤ 70. |
| output |
| An integer that represents the result of a different selection scheme number modulo 1000000007. |
| Input Example |
| 6 19 4 18776  /td> |
| Output Example |
| 116280  |
|
#include <cstdio>
#include <iostream>
#define MOD 1000000007
#define LL Long Long
using namespace Std;
LL ans;
int n,m,mx,mn;
int main ()
{
scanf ("%d%d%d%d", &n,&m,&mn,&mx);
for (int i=3;i<=n;i++)
for (int j=3;j<=m;j++)
{
int w=2* (I+J-2);
if (w<=mx&&w>=mn) ans+= (LL) (n-i+1) * (m-j+1) * (i-2) * (j-2)%mod;
}
printf ("%lld\n", (ans*6)%mod);
}
Tibetan Sister (Excel) (c + +) Password: none
