Сдвиг столбцов матрицы на заданную позицию влево

const n=5;
m=4;
type mas=array[1..n,1..m] of integer;

procedure Vvod(var v:mas);
var i,j:integer;
begin
for i:=1 to n do
for j:=1 to m do
v[i,j]:=random(100)-50;
end;

procedure Vyvod(var v:mas);
var i,j:integer;
begin
for i:=1 to n do begin
for j:=1 to m do begin
write(v[i,j]:4);
end;
writeln;
end;
writeln;
end;

procedure Sdvigstrochka(var a:mas;k:integer);
var i,j,x:integer;
begin

for i:=1 to n do
begin
x:=a[i,1];
for j:=1 to m-1 do
begin
a[i,j]:=a[i,j+1];
end;
a[i,m]:=x;
end;
writeln('Rezultat:');
for i:=1 to n do
begin
for j:=1 to m do
write(a[i,j]:4);
writeln;
end;

end;



var a,b:mas;
begin
Vvod(a);
Vyvod(a);
Sdvigstrochka(a,1);
end.