View Compilation Error

0_0_27268622_13872.cpp: In function 'void solve()':
0_0_27268622_13872.cpp:69:16: error: expected primary-expression before '?' token
 for (cnt = 1 ; ?; ++cnt)
                ^
0_0_27268622_13872.cpp:69:17: error: expected primary-expression before ';' token
 for (cnt = 1 ; ?; ++cnt)
                 ^
0_0_27268622_13872.cpp:69:17: error: expected ':' before ';' token
0_0_27268622_13872.cpp:69:17: error: expected primary-expression before ';' token