Alice and Bob have a lawn in front of their house, shaped like an meter by meter rectangle. Each year, they try to cut the lawn in some interesting pattern. They used to do their cutting with shears, which was very time-consuming; but now they have a new automatic lawnmower with multiple settings, and they want to try it out.
The new lawnmower has a height setting - you can set it to any height between 1 and 100 millimetres, and it will cut all the grass higher than it encounters to height . You run it by entering the lawn at any part of the edge of the lawn; then the lawnmower goes in a straight line, perpendicular to the edge of the lawn it entered, cutting grass in a swath 1m wide, until it exits the lawn on the other side. The lawnmower's height can be set only when it is not on the lawn.
Alice and Bob have a number of various patterns of grass that they could have on their lawn. For each of those, they want to know whether it's possible to cut the grass into this pattern with their new lawnmower. Each pattern is described by specifying the height of the grass on each 1m x 1m square of the lawn.
The grass is initially 100mm high on the whole lawn.
Input Specification
The first line of the input gives the number of test cases, . test cases follow. Each test case begins with a line containing two integers: and . Next follow lines, with the th line containing integers each, the number describing the desired height of the grass in the th square of the th row.
Output Specification
For each test case, output one line containing Case #x: y
, where is the case number (starting from 1) and is either the word YES
if it's possible to get the pattern using the lawnmower, or NO
, if it's impossible.
Limits
Time limit: 30 seconds per test set.
Memory limit: 1GB.
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Small dataset
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Large dataset
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Sample Input
3
3 3
2 1 2
1 1 1
2 1 2
5 5
2 2 2 2 2
2 1 1 1 2
2 1 2 1 2
2 1 1 1 2
2 2 2 2 2
1 3
1 2 1
Sample Output
Case #1: YES
Case #2: NO
Case #3: YES
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