C++ vector中所有元素快速置零

vector元素置零方法有很多种，其中比较快的是std::fill

const int n = 10000;
vector<int> v(n, 0);
/*
modify vector
.
.
.
*/
//here we want to set all value in the vector to zero
std::fill(v.begin(), v.end(), 0);

当然还可以使用iterator迭代置零，或者assign置零，memset置零

const int n = 10000;
vector<int> v(n, 0);
/*
modify vector
.
.
.
*/
memset(&v[0], 0, v.size() * sizeof v[0]);
//or
v.assign(v.size(), 0);
//or	
for (auto it=v.begin(); it!=v.end(); ++it) {
   *it = 0;
}