program permutation; var i,j : integer; a : array [1..3 , 1..3] of integer; procedure permute ( var a,b : integer ); var c : integer; begin c:=a; a:=b; b:=c; end; begin for i := 1 to 3 do for i:= 1 to 3 do begin writeln(' donnez les de m[',i,'.',j,'] '); readln (a[i,j]); end; for i := 1 to 3 do permute ( a[i,i] , a[3-i,i]); writeln; for i:= 1 to 3 do for j:= 1 to 3 do begin writeln( a[i,j]); end; readln; end.