i = 1

S = 0？ (Error: S= 1)

n = 0

And S<= 500? (error: DO)

S = S + i

i = i + 1

n = n + 1

line

Print n? (Error: n+ 1)

end

In fact, in the algorithm given in this question, the functions of variables n and I are similar, and one can be completely removed to make the algorithm simpler:

The following flow chart is better: