View Compilation Error

0_0_30412043_17405.cpp: In function 'int main()':
0_0_30412043_17405.cpp:21:34: error: expected ')' before ';' token
 while(cin >> x1 >> y1 >> x2 >> y2;)
                                  ^
0_0_30412043_17405.cpp:21:35: error: expected primary-expression before ')' token
 while(cin >> x1 >> y1 >> x2 >> y2;)
                                   ^