MATSUM - Matrix Summation
A N × N matrix is filled with numbers. BuggyD is analyzing the matrix, and he wants the sum of certain submatrices every now and then, so he wants a system where he can get his results from a query. Also, the matrix is dynamic, and the value of any cell can be changed with a command in such a system.
Assume that initially, all the cells of the matrix are filled with 0. Design such a system for BuggyD. Read the input format for further details.
The first line of the input contains an integer t, the number of test cases. t test cases follow.
The first line of each test case contains a single integer N (1 <= N <= 1024), denoting the size of the matrix.
A list of commands follows, which will be in one of the following three formats (quotes are for clarity):
- "SET x y num" - Set the value at cell (x, y) to num (0 <= x, y < N).
- "SUM x1 y1 x2 y2" - Find and print the sum of the values in the rectangle from (x1, y1) to (x2, y2), inclusive. You may assume that x1 <= x2 and y1 <= y2, and that the result will fit in a signed 32-bit integer.
- "END" - Indicates the end of the test case.
For each test case, output one line for the answer to each "SUM" command. Print a blank line after each test case.
Input: 1 4 SET 0 0 1 SUM 0 0 3 3 SET 2 2 12 SUM 2 2 2 2 SUM 2 2 3 3 SUM 0 0 2 2 END Output: 1 12 12 13
things to keep in mind
Iterative 2D segment tree passed without problems.
No matter how much optimisation is done, 2-D segment tree isn't working. Time Limit is too strict for it.
getting tle after using int ,scanf,printf,fastio,BIT , plz someone help
Things to look out for:
I learned 2D BIT by this problem. Actually I didn't learn from somewhere. I got the idea myself. I feel like I'm a genius :-) ha ha.
Its giving TLE in JAVA using 2D segment tree. Doesn't SPOJ provide extra time for slow languages like JAVA?
use scanf & printf instead :), if u got TLE in spite of your right algorithm
Isn't it really possible to get AC using Segment tree in CPP? Is there anybody? Please share what you have done?
in java, it is giving TLE using 2D BIT...please suggest what to do