解题思路
类比一维差分, 原数组a[i][j], 差分数组b[i][j];
b[x1][y1] += c; b[x2 + 1][y1] -= c; b[x1][y2 + 1] -= c; b[x2 + 1][y2 + 1] += c;
算法1
C++ 代码
#include <iostream>
using namespace std;
const int N = 1010;
int n, m, q;
int a[N][N], b[N][N];
void insert(int x1, int y1, int x2, int y2, int c)
{
b[x1][y1] += c;
b[x1][y2 + 1] -= c;
b[x2 + 1][y1] -= c;
b[x2 + 1][y2 + 1] += c;
}
int main()
{
scanf("%d %d %d", &n, &m, &q);
for(int i = 1; i <= n; i ++ )
for(int j = 1; j <= m; j ++ )
scanf("%d", &a[i][j]);
for(int i = 1; i <= n; i ++ )
for(int j = 1; j <= m; j ++ )
insert(i, j, i, j, a[i][j]);
while(q -- )
{
int x1, y1, x2, y2, c;
scanf("%d %d %d %d %d", &x1, &y1, &x2, &y2, &c);
insert(x1, y1, x2, y2, c);
}
for(int i = 1; i <= n; i ++ )
for(int j = 1; j <= m; j ++ )
b[i][j] += b[i - 1][j] + b[i][j - 1] - b[i - 1][j - 1];
for(int i = 1; i <= n; i ++ )
{
for(int j = 1; j <= m; j ++ )
printf("%d ", b[i][j]);
puts("");
}
return 0;
}