Icon is another language invented by Ralph Griswold the inventor of Snobol4. This program does not demonstrate the exotic features of this language, but it does give a taste of the code structure.
This program compiles and runs under the University of Arizona Icon compiler..
procedure main()
local i,j,Candidates
Candidates := table()
every i := 0 to 1000 do
Candidates[i] := 1
i := 0
Candidates[0] := 0
Candidates[1] := 0
while i<1000 do {
while i<1000 & Candidates[i] = 0 do
i := i + 1
if i < 1000 then {
j := 2
while (i*j) < 1000 do {
Candidates[i*j] := 0
j := j + 1
}
i := i + 1
}
}
write("prime list")
every i := 0 to 999 do {
if Candidates[i] ~= 0 then {
write(i," is prime")
}
}
end