View Compilation Error

0_0_14165464_17395.cpp: In function 'int main()':
0_0_14165464_17395.cpp:100:12: error: expected primary-expression before 'while'
     while (while cas--)
            ^
0_0_14165464_17395.cpp:100:12: error: expected ')' before 'while'
0_0_14165464_17395.cpp:100:18: error: expected '(' before 'cas'
     while (while cas--)
                  ^