View Compilation Error

0_0_25749488_26246.cpp: In function 'll china(int)':
0_0_25749488_26246.cpp:73:29: error: 'qumul' was not declared in this scope
   x = (x + qumul(qumul(y,w,M),a[i],M)) % M;
                             ^
0_0_25749488_26246.cpp:73:37: error: 'qumul' was not declared in this scope
   x = (x + qumul(qumul(y,w,M),a[i],M)) % M;
                                     ^
0_0_25749488_26246.cpp:73:37: error: redeclaration of '<typeprefixerror>qumul'
0_0_25749488_26246.cpp:73:29: note: previous declaration '<typeprefixerror>qumul'
   x = (x + qumul(qumul(y,w,M),a[i],M)) % M;
                             ^