/in/foo.cc: In function 'int main()':
/in/foo.cc:6:30: warning: variable 'min' set but not used [-Wunused-but-set-variable]
  int i,j,t,max=0,k,x,y,x1,y1,min=100,sum=0;
                              ^~~
/in/foo.cc:22:14: warning: 'y' may be used uninitialized in this function [-Wmaybe-uninitialized]
   x1=a[x+1][y]>a[x-1][y]? x+1:x-1;
      ~~~~~~~~^
/in/foo.cc:24:14: warning: 'x' may be used uninitialized in this function [-Wmaybe-uninitialized]
   sum+=a[x][y]+a[x][y1]+a[x1][y]+a[x1][y1]*k;
        ~~~~~~^