foo.cpp: In function 'int main()':
foo.cpp:6:16: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   x[1]=1;y[1]=n+1>>1;ma[x[1][y[1]]=1;
                ^
foo.cpp:6:34: error: invalid types 'int[int]' for array subscript
   x[1]=1;y[1]=n+1>>1;ma[x[1][y[1]]=1;
                                  ^
foo.cpp:6:37: error: expected ']' before ';' token
   x[1]=1;y[1]=n+1>>1;ma[x[1][y[1]]=1;
                                     ^