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See all the blocks
In a 3D coordinates, a block (a,b,c) takes the place of x<a<x+1, b<y<b+1, c<z<c+1.
Is there a point that can see every block? (Exist point P, For each block K exist point Q, segment PQ don't go across any block but K)
Is there a way that can see every block? (Exist non-zero...