tengo un problema, en general el juego funciona pero no puedo lograr que salga el mensaje de que ya gane 
Código (c) [Seleccionar]
#include <stdio.h>
#include <stdlib.h>
#include <conio.h>
#include <windows.h>
#include <time.h>
void gotoxy(short x, short y){
COORD pos = {x , y};
SetConsoleCursorPosition(GetStdHandle(STD_OUTPUT_HANDLE),pos);}
main()
{
int r, x, y, j, vm, k, v,i;
int a[16], b[4][4],c[4][4];
srand (time(NULL));
for (i=0; i<=14; i++) {
a[i] = rand()%(14+1);
}
r = 1;
while (r == 1) {
r = 0;
for (i=0; i<=14; i++) {
if (a[i]==0)
a[i]++;
for (j=i+1; j<=14; j++)
{
if (a[i] == a[j] && a[i] !=15) {
a[i] = a[i] +1;
r = 1;
}
if (a[i] == a[j] && a[i] ==15) {
a[i] = a[i] -rand()%(14+1);
r = 1; }
}}}
j=0;
for (x=0; x<=3; x++) {
for(y=0; y<=3; y++)
{b[x][y]=a[j];j++;
}}
x=3;
y=3;
fflush(stdin);
b[3][3]=0;
c[0][0]=1;
c[0][1]=2;
c[0][2]=3;
c[0][3]=4;
c[1][0]=5;
c[1][1]=6;
c[1][2]=7;
c[1][3]=8;
c[2][0]=9;
c[2][1]=10;
c[2][2]=11;
c[2][3]=12;
c[3][0]=13;
c[3][1]=14;
c[3][2]=15;
c[3][3]=0;
do{
///////////////////IZQ////////////////////
gotoxy(1,2);printf("%c",201);
gotoxy(1,3);printf("%c",186);
gotoxy(1,4);printf("%c",204);
gotoxy(1,5);printf("%c",186);
gotoxy(1,6);printf("%c",186);
gotoxy(1,7);printf("%c",186);
gotoxy(1,8);printf("%c",204);
gotoxy(1,9);printf("%c",186);
gotoxy(1,10);printf("%c",200);
///////////////////DER////////////////////
gotoxy(13,2);printf("%c",187);
gotoxy(13,3);printf("%c",186);
gotoxy(13,4);printf("%c",185);
gotoxy(13,5);printf("%c",186);
gotoxy(13,6);printf("%c",186);
gotoxy(13,7);printf("%c",186);
gotoxy(13,8);printf("%c",185);
gotoxy(13,9);printf("%c",186);
gotoxy(13,10);printf("%c",188);
///////////////////Arriba////////////////////
gotoxy(2,2);printf("%c",205);
gotoxy(3,2);printf("%c",205);
gotoxy(4,2);printf("%c",203);
gotoxy(5,2);printf("%c",205);
gotoxy(6,2);printf("%c",205);
gotoxy(7,2);printf("%c",203);
gotoxy(8,2);printf("%c",205);
gotoxy(9,2);printf("%c",205);
gotoxy(10,2);printf("%c",203);
gotoxy(11,2);printf("%c",205);
gotoxy(12,2);printf("%c",205);
//////////////////ABAJO/////////////////////
gotoxy(2,10);printf("%c",205);
gotoxy(3,10);printf("%c",205);
gotoxy(4,10);printf("%c",202);
gotoxy(5,10);printf("%c",205);
gotoxy(6,10);printf("%c",205);
gotoxy(7,10);printf("%c",202);
gotoxy(8,10);printf("%c",205);
gotoxy(9,10);printf("%c",205);
gotoxy(10,10);printf("%c",202);
gotoxy(11,10);printf("%c",205);
gotoxy(12,10);printf("%c",205);
/////////////////linea 1///////////////////
gotoxy(4,3);printf("%c",186);
gotoxy(4,4);printf("%c",206);
gotoxy(4,5);printf("%c",186);
gotoxy(4,6);printf("%c",206);
gotoxy(4,7);printf("%c",186);
gotoxy(4,8);printf("%c",206);
gotoxy(4,9);printf("%c",186);
/////////////////linea 2///////////////////
gotoxy(7,3);printf("%c",186);
gotoxy(7,4);printf("%c",206);
gotoxy(7,5);printf("%c",186);
gotoxy(7,6);printf("%c",206);
gotoxy(7,7);printf("%c",186);
gotoxy(7,8);printf("%c",206);
gotoxy(7,9);printf("%c",186);
/////////////////linea 3///////////////////
gotoxy(10,3);printf("%c",186);
gotoxy(10,4);printf("%c",206);
gotoxy(10,5);printf("%c",186);
gotoxy(10,6);printf("%c",206);
gotoxy(10,7);printf("%c",186);
gotoxy(10,8);printf("%c",206);
gotoxy(10,9);printf("%c",186);
//////////////////ABAJO 1/////////////////////
gotoxy(2,4);printf("%c",205);
gotoxy(3,4);printf("%c",205);
gotoxy(4,4);printf("%c",206);
gotoxy(5,4);printf("%c",205);
gotoxy(6,4);printf("%c",205);
gotoxy(7,4);printf("%c",206);
gotoxy(8,4);printf("%c",205);
gotoxy(9,4);printf("%c",205);
gotoxy(10,4);printf("%c",206);
gotoxy(11,4);printf("%c",205);
gotoxy(12,4);printf("%c",205);
//////////////////ABAJO 1/////////////////////
gotoxy(2,6);printf("%c",205);
gotoxy(3,6);printf("%c",205);
gotoxy(4,6);printf("%c",206);
gotoxy(5,6);printf("%c",205);
gotoxy(6,6);printf("%c",205);
gotoxy(7,6);printf("%c",206);
gotoxy(8,6);printf("%c",205);
gotoxy(9,6);printf("%c",205);
gotoxy(10,6);printf("%c",206);
gotoxy(11,6);printf("%c",205);
gotoxy(12,6);printf("%c",205);
//////////////////ABAJO 1/////////////////////
gotoxy(2,8);printf("%c",205);
gotoxy(3,8);printf("%c",205);
gotoxy(4,8);printf("%c",206);
gotoxy(5,8);printf("%c",205);
gotoxy(6,8);printf("%c",205);
gotoxy(7,8);printf("%c",206);
gotoxy(8,8);printf("%c",205);
gotoxy(9,8);printf("%c",205);
gotoxy(10,8);printf("%c",206);
gotoxy(11,8);printf("%c",205);
gotoxy(12,8);printf("%c",205);
////////////////////////////////////////////
/////////////////////////
gotoxy(2,3);printf("%d",b[0][0]);
gotoxy(5,3);printf("%d",b[0][1]);
gotoxy(8,3);printf("%d",b[0][2]);
gotoxy(11,3);printf("%d",b[0][3]);
gotoxy(2,5);printf("%d",b[1][0]);
gotoxy(5,5);printf("%d",b[1][1]);
gotoxy(8,5);printf("%d",b[1][2]);
gotoxy(11,5);printf("%d",b[1][3]);
gotoxy(2,7);printf("%d",b[2][0]);
gotoxy(5,7);printf("%d",b[2][1]);
gotoxy(8,7);printf("%d",b[2][2]);
gotoxy(11,7);printf("%d",b[2][3]);
gotoxy(2,9);printf("%d",b[3][0]);
gotoxy(5,9);printf("%d",b[3][1]);
gotoxy(8,9);printf("%d",b[3][2]);
gotoxy(11,9);printf("%d",b[3][3]);
//////////////////////////////////////
vm=getch();
system("cls");
switch(vm)
{
case 80: //FLECHA DERECHA
if(x <= 2){
v=b[x+1][y];
b[x][y]=v;
b[x+1][y]=0;
x++;
}
break;
case 72: //FLECHA IZQUIERDA
if(x>0)
{
v=b[x-1][y];
b[x-1][y]=0;
b[x][y]=v;
x--;
}
break;
case 77: //FLECHA ABAJO
if(y <= 2)
{
v=b[x][y+1];
b[x][y+1]=0;
b[x][y]=v;
y++;
}
break;
case 75: //FLECHA ARRIBA
if(y > 0)
{
v=b[x][y-1];
b[x][y-1]=0;
b[x][y]=v;
y--;
}
break;
} }while(vm!=13);
}