View Compilation Error

0_0_28978509_21479.cpp: In function 'int main()':
0_0_28978509_21479.cpp:19:4: error: expected primary-expression before '?' token
    ?sum=sum+maxx-a[i];
    ^
0_0_28978509_21479.cpp:19:22: error: expected ':' before ';' token
    ?sum=sum+maxx-a[i];
                      ^
0_0_28978509_21479.cpp:19:22: error: expected primary-expression before ';' token