0_0_16782723_27150.cpp:4:1: error: '_int64' does not name a type _int64 C(int n,int m) ^ 0_0_16782723_27150.cpp: In function 'int main()': 0_0_16782723_27150.cpp:25:23: error: 'C' was not declared in this scope s=a[m]*C(n,n-m); ^