Manipulate in MATHEMATICA

[ramprasad]

Dear all,

I am trying to implement an algorithm using manipulate environment. But its not working properly. Kindly figure out the error.
The same code outside manipulate works fine. Following are the codes.

Without manipulate
Module[{G, f, h, n, A, p}, Off[]; G[t_, s_] := s(t - 1);
f[0][t_] := t^2;
h[t_] := Sin[t]; n = 3; a = 0; b = 5;
f[1][t_] := Integrate[G[t, s]h[f[0][t]],
{s, 0, 1}];
Do[f[i + 1][t] = Integrate[G[t, s]*h[f[t]], {s, 0, 1}], {i, n}];
Do[Print[Panel[f[t]]], {i, n}]; p[k_] := f[k][t];
A = Array[p, {n}];
Plot[A, {t, a, b}]]

Inside manipulate
Manipulate[
Module[{G, f, h, n, A, p}, Off[]; G[t_, s_] := Gr; f[0][t_] := g;
h[t_] := r; n = 3;
f[1][t_] := Integrate[G[t, s]h[f[0][t]], {s, 0, 1}];
Do[f[i + 1][t] = Integrate[G[t, s]h[f[t]], {s, 0, 1}], {i,
n}];
Do[Print[Panel[f[t]]], {i, n}]; p[k_] := f[k][t];
A = Array[p, {n}];
Plot[A, {t, a, b}]], {{Gr, s*(t - 1), "Green's Function"}},
{{r, Sin[t], "Function in RHS"}}, {{g, t^2,
"First Guess Solution"}},
{{a, 0, "Left extreme of interval"}}, {{b, 5,
"Right extreme of interval"}},
TrackedSymbols -> True, AutorunSequencing -> {1}]

Regards,
Ramprasad