CareerCup

I don't quite understand your question, can you elaborate a little bit?

From my understanding of the question, if w and z are the lengths of the sides of the rectangle, the probability should be: 2/((w+1)*(z+1)), given that (x,y) can only be integer co-ordinates.

The idea behind this is simple. The total no. of integral co-ordinates in a rectangle of w,z dimensions are (w+1)*(z+1), including the end-points. Now, the guy can only fall of the island if hes on any one of those 4 points, and makes 2 wrong directions (for eg. west and north at the top left point) at each of these 4 points.

Thus, number of deathly moves= 4*2=8

Total number of possible moves= (w+1)*(z+1)*4, since at each point i can move in 4 directions.

Thus, probability of the guy dying is: 2/((w+1)*(z+1)).

Question is NOT clear... I repeat NOT CLEAR

the question look intresting.. but the information given is not sufficient.. some1 please eleborate the question

this question is easy DP problem just for each state store the prob of reaching that block.
each block can be reach from 4 direction so dp[i][j][k]=dp[i-1][j][k-1]/4+dp[i+1][j][k-1]/4+dp[i][j-1][k-1]/4+dp[i][j+1][k]/4;
if check condition if all those lie on island and then add all prob of bloacks on island that is his living probability.