View Compilation Error

0_0_21699286_19695.cpp: In function 'int main()':
0_0_21699286_19695.cpp:13:22: error: expected '(' before '{' token
                 while{n--}
                      ^
0_0_21699286_19695.cpp:13:22: error: expected primary-expression before '{' token
0_0_21699286_19695.cpp:13:22: error: expected ')' before '{' token
0_0_21699286_19695.cpp:13:26: error: expected ';' before '}' token
                 while{n--}
                          ^
0_0_21699286_19695.cpp:20:1: error: expected ';' before '}' token
 }
 ^