#################################################
# Spring 2025 Valentine Submission - Pablo Blanco
# Uses the GraphTheory package to draw a heart.
#################################################

with(GraphTheory):
LoveGraph:=proc(n) local E,G,vp,i,hgt:
 hgt:= 1.1: # height factor
 E:={seq({i,i+1},i=1..2*n+5),{1,2*n+6}, #heart outline
 {n+2,2*n+4}, {n+2,2*n+6}, {2*n+6,2*n+4}, {n+2,2*n+3},{n+2,1}
 }:
 G:=Graph(2*n+6,E):
 vp:=[[2,0],
 seq(evalf([cos(3.141*(i)/(n+1))+1,hgt*sin(3.141*(i)/(n+1))]) ,i=1..n),
 [0,0],
 seq(evalf([cos(3.141*(i)/(n+1))-1,hgt*sin(3.141*(i)/(n+1))]) ,i=1..n),
[-2,0], 
[-1,-hgt^2],[0,-2*hgt^2], # bottom heart tip

[1,-hgt^2]]:
 
 
 SetVertexPositions(G,vp):
 G:
end:

n:=80: ## change this to increase or decrease heart resolution.
G:=LoveGraph(n):

HighlightEdges(G,[seq({i,i+1},i=1..2*n+5),{1,2*n+6}],stylesheet=[color="Red", thickness=3]):
DrawGraph(G,stylesheet=[vertexcolor="Pink"]);
print(`I love Algorithmic Graph Theory!`);