View Compilation Error

0_0_25299704_11822.cpp: In function 'int main()':
0_0_25299704_11822.cpp:30:25: error: lvalue required as decrement operand
             int x=read()--,y=read()--,z=read();
                         ^
0_0_25299704_11822.cpp:32:17: error: 'z' was not declared in this scope
             if (z<dst[x][y]) dst[x][y]=dst[y][x]=z;
                 ^
0_0_25299704_11822.cpp:32:26: error: 'y' was not declared in this scope
             if (z<dst[x][y]) dst[x][y]=dst[y][x]=z;
                          ^