配列の総和
/* template<class _InIt, class _Ty> _Ty accumulate(_InIt _First, _InIt _Last, _Ty _Val) template<class _InIt, class _Ty, class _Fn2> _Ty _Accumulate(_InIt _First, _InIt _Last, _Ty _Val, _Fn2 _Func) */ #include <numeric> #include <functional> #include <iostream> using namespace std; int main() { int a[] = {1,4,9}; // 0+1+4+9 = 14 cout << accumulate( a, a+3, 0 ) << endl; // 1*1*4*9 = 36 cout << accumulate( a, a+3, 1, multiplies<int>() ) << endl; return 0; }