Prefix sum and difference

The prefix and

One dimensional prefix and preprocessing ：

sum[i]=sum[i-1]+a[i];

Two dimensional prefix and preprocessing template ：

sum[i][j]=sum[i-1][j]+sum[i][j-1]-sum[i-1][j-1]+a[i][j];

Difference

One dimensional difference

// to l~r Add all the numbers of the interval x
d[l]+=x;
d[r+1]-=x;

Two dimensional difference

// Give (x1,y1) It's the upper left corner ,(x2,y2) Add all the numbers in the lower right corner x
d[x1][y1]+=x;
d[x2+1][y1=-=x;
d[x1][y2+1]-=x;
d[x2+1][y2+1]+=x;