how to draw the cdf and pdf of a this multinomial distribution

clc clear all format compact rng(970,'v4') X1=[]; X2=[]; X3=[]; U=[]; Y=[]; p =[0.0080 0.0270 0.1250 0.0360 0.0600 0.1350 0.2250 0.0540 0.1500 0.1800]; n = 3; for i = (1:10000) r=rand;

   if r<0 & r<=0.0080
         x1(i)=0; x2(i)=0; x3(i)=3;
         y(i)=1;
       X1=[x1];X2=[x2];X3=[x3];
       Y=[y];
       U=[U,r];
   else if r>0.0080 & r<=0.0350
           x1(i)=0; x2(i)=3; x3(i)=0;
           y(i)=2;
           X1=[x1];X2=[x2];X3=[x3];
            Y=[y];
           U=[U,r];
       else if r>0.0350 & r<=0.1600
               x1(i)=3; x2(i)=0; x3(i)=0;
               y(i)=3;
               X1=[x1];X2=[x2];X3=[x3];
               Y=[y];
               U=[U,r];
           else if r>0.1600 & r<=0.1960
                   x1(i)=0; x2(i)=1; x3(i)=2;
                  y(i)=4;
                   X1=[x1];X2=[x2];X3=[x3];
                    Y=[y];
                   U=[U,r];
               else if r>0.1960 & r<=0.2560
                       x1(i)=1; x2(i)=0; x3(i)=2;
                      y(i)=5;
                       X1=[x1];X2=[x2];X3=[x3];
                        Y=[y];
                       U=[U,r];
                   else if r>0.2560 & r<=0.3910
                           x1(i)=1; x2(i)=2; x3(i)=0;
                          y(i)=6;
                           X1=[x1];X2=[x2];X3=[x3];
                            Y=[y];
                           U=[U,r];
                       else if r>0.3910 & r<=0.6160
                               x1(i)=2; x2(i)=1; x3(i)=0;
                             y(i)=7;
                               X1=[x1]; X2=[x2]; X3=[x3];
                               Y=[y];
                               U=[U,r];
                           else if r>0.6160 & r<=0.6700
                                   x1(i)=0; x2(i)=2; x3(i)=1;
                                  y(i)=8;
                                   X1=[x1];X2=[x2];X3=[x3];
                                    Y=[y];
                                   U=[U,r];
                               else if r>0.6700 & r<=0.8200
                                       x1(i)=2; x2(i)=0; x3(i)=1;
                                       y(i)=9;
                                       X1=[x1];X2=[x2];X3=[x3];
                                       Y=[y];
                                       U=[U,r];
                                   else if r>0.8200 & r<=1
                                           x1(i)=1; x2(i)=1; x3(i)=1;
                                         y(i)=10;
                                           X1=[x1];X2=[x2];X3=[x3];
                                             Y=[y];
                                           U=[U,r];
                                       end
                                   end
                               end
                           end
                       end
                   end
               end
           end
       end
   end
end