View Compilation Error

0_0_13088324_9601.cpp: In function 'int main()':
0_0_13088324_9601.cpp:9:24: error: expected ')' before '!' token
     while(scanf("%s",a)!a=EOF)
                        ^
0_0_13088324_9601.cpp:9:26: error: lvalue required as left operand of assignment
     while(scanf("%s",a)!a=EOF)
                          ^