View Compilation Error

0_0_26989633_3989.cpp: In function 'int main()':
0_0_26989633_3989.cpp:12:27: error: expected primary-expression before ',' token
         scanf("%d%d%d%d", ,&n, &A, &B, &L);
                           ^
0_0_26989633_3989.cpp:17:32: error: missing template arguments before ';' token
             if(a>b) conditional;
                                ^