Given points
p [ 0 ] . first = 4 , p [ 0 ] . second = 0 ; p [ 1 ] . first = 0 , p [ 1 ] . second = 2 ; p [ 2 ] . first = -1 , p [ 2 ] . second = -7 ; p [ 3 ] . first = 1 , p [ 3 ] . second = 10 ; p [ 4 ] . first = 2 , p [ 4 ] . second = -3 ;