Good Bye 2015 C. New Year and Domino dp+容斥原理

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C. New Year and Domino
time limit per test
3 seconds
memory limit per test
256 megabytes
input
standard input
output
standard output

They say "years are like dominoes, tumbling one after the other". But would a year fit into a grid? I don't think so.

Limak is a little polar bear who loves to play. He has recently got a rectangular grid withh rows and w columns. Each cell is a square, either empty (denoted by '.') or forbidden (denoted by '#'). Rows are numbered 1 through h from top to bottom. Columns are numbered 1 through w from left to right.

Also, Limak has a single domino. He wants to put it somewhere in a grid. A domino will occupy exactly two adjacent cells, located either in one row or in one column. Both adjacent cells must be empty and must be inside a grid.

Limak needs more fun and thus he is going to consider some queries. In each query he chooses some rectangle and wonders, how many way are there to put a single domino inside of the chosen rectangle?

Input

The first line of the input contains two integers h andw (1 ≤ h, w ≤ 500) – the number of rows and the number of columns, respectively.

The next h lines describe a grid. Each line contains a string of the lengthw. Each character is either '.' or '#' — denoting an empty or forbidden cell, respectively.

The next line contains a single integer q (1 ≤ q ≤ 100 000) — the number of queries.

Each of the next q lines contains four integersr1i,c1i,r2i,c2i (1 ≤ r1i ≤ r2i ≤ h, 1 ≤ c1i ≤ c2i ≤ w) — the i-th query. Numbers r1i andc1i denote the row and the column (respectively) of the upper left cell of the rectangle. Numbersr2i andc2i denote the row and the column (respectively) of the bottom right cell of the rectangle.

Output

Print q integers, i-th should be equal to the number of ways to put a single domino inside thei-th rectangle.

Sample test(s)
Input
5 8....#..#.#......##.#....##..#.##........41 1 2 34 1 4 11 2 4 52 5 5 8
Output
401015
Input
7 39........................................###..###..#..###.....###..###..#..###....#..#.#..#..#.........#..#.#..#..#....###..#.#..#..###.....###..#.#..#..###..#....#.#..#....#.....#....#.#..#..#.#..###..###..#..###.....###..###..#..###........................................61 1 3 202 10 6 302 10 7 302 2 7 71 7 7 71 8 7 8
Output
53891202302
Note

A red frame below corresponds to the first query of the first sample. A domino can be placed in 4 possible ways.

题意:给出一个图,q次询问,每次询问这个图的某一个矩形区域装下一个长为1宽为2的矩形的方法有多少种。

思路:dp+容斥原理

#include <stdio.h>#include <string.h>#include <iostream>#include <algorithm>#include <vector>#include <queue>#include <set>#include <map>#include <string>#include <math.h>#include <stdlib.h>#include <time.h>using namespace std;char Map[505][505];int dp[505][505];int h, w, q, r1, c1, r2, c2;int main(){    int i, j, res;    scanf("%d %d", &h, &w);    for(int i = 0;i < h;i++)        scanf("%s", Map[i]);    for(i = 0;i < h;i++)        if(i - 1 >= 0&&Map[i-1][0] == '.'&&Map[i][0] == '.') dp[i][0] = dp[i-1][0] + 1;        else dp[i][0] = dp[i-1][0];    for(i = 0;i < w;i++)        if(i - 1 >= 0&&Map[0][i-1] == '.'&&Map[0][i] == '.') dp[0][i] = dp[0][i-1] + 1;        else dp[0][i] = dp[0][i-1];    for(i = 1;i < h;i++)    {        for(j = 1;j < w;j++)        {            dp[i][j] += dp[i - 1][j];            dp[i][j] += dp[i][j - 1];            if(Map[i][j] == '.'){                if(Map[i-1][j] == '.') dp[i][j]++;                if(Map[i][j-1] == '.') dp[i][j]++;            }            dp[i][j] -= dp[i-1][j-1];        }    }    scanf("%d", &q);    while(q--){        scanf("%d %d %d %d", &r1, &c1, &r2, &c2);        //printf("%d %d", r2-r1-1, c2-c1-1);        res = dp[r2-1][c2-1] - dp[r1-1][c2-1] - dp[r2-1][c1-1] + dp[r1-1][c1-1];        for(i = r1-1;i <= r2-1;i++) if(i-1>=r1-1&&Map[i-1][c1-1]=='.'&&Map[i][c1-1]=='.') res++;        for(i = c1-1;i <= c2-1;i++) if(i-1>=c1-1&&Map[r1-1][i-1]=='.'&&Map[r1-1][i]=='.') res++;        printf("%d\n", res);    }}





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