MMCC '15 P2 - Akame
View as PDFAkame is training on an infinite 2D Cartesian plane. There is an infinitely long rigid and vertical string at each integer x-coordinate. She takes out her katana, Murasame, and makes  infinitely long slashes on the plane. Each slash can be seen as a line with the equation 
, for some 
, 
, and 
. A slash will never be a vertical line.
Each string Akame slashes will immediately be broken into two smaller strings. For example, a string originally from  to 
 severed by the line 
 will be broken into the two strings 
 to 
 and 
 to 
. A string is considered disconnected if it is of a finite length. For example, the string from 
 to 
 is not of finite length, but the string from 
 to 
 is.
There are  points on strings Akame wants to disconnect. A point is said to be disconnected if it is either slashed or the string it's on is disconnected. To measure her performance, Akame would like to know the earliest moment (that is, after which slash) each point is disconnected. The slashes are numbered from 
 to 
.
Input Specification
The first line of input will have  and 
, separated by a single space.
The next  lines of input will each describe one of Akame's slashes, with 
, 
, and 
 separated by spaces.
The next  lines of input will each describe a point Akame wants to disconnect, with 
 and 
.
Output Specification
There should be  lines of output. The 
 line should contain the smallest index of the slash that after it is performed, the 
 point is disconnected. If the 
 point is never disconnected, print 
-1 instead.
Constraints
Sample Input 1
3 5
0 1 3
0 1 5
0 1 7
1 2
1 3
1 4
1 5
1 6
Sample Output 1
-1
1
2
2
3
Sample Input 2
10 10
81 -36 72
64 -69 24
23 47 47
83 36 18
1 25 77
12 -81 -3
13 -90 -34
23 19 -34
19 23 78
50 -96 82
56 59
85 47
46 -23
1 13
-74 -69
23 99
-98 72
-31 -65
-78 76
9 -69
Sample Output 2
2
3
4
-1
2
-1
4
2
4
-1
Comments
It seems that some of tests have
, can you please fix this problem (I submitted a program which exits on zero input and has an infinite loop on other inputs, there are a couple of tests where I get WA, so they have 
)?