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My code doesn't work and i can't figure out whats wrong with it.
program p;
var
a,b,m,n,nn:integer;
Ar:array[0..101,0..101] of integer;
c:char;
begin
nn:=1;
readln(m,n);
for a:=0 to 101 do
for b:=0 to 101 do
Ar[a,b]:=0;
while (n<>0) and (m<>0) do begin
for a:=1 to M do begin
for b:=1 to N do begin ...