I'm implementing DS in C++ that support regular get() and set() plus set_all() in O(1).

For that I saved for each element a time strap of when it was updated the last time and compared it to when I lastly updated the set_all variable.

The problem is that I used std::time to measure time which wasn't good enough as hundreds of operations could occur in same time.

How can I solve this?

class evector {
    vector<int> vec;
    vector<time_t> t_straps;
    int g_val = 0;
    time_t g_strap = 0;

public:
    explicit evector(int size, int init_val = 0) : vec(size, init_val), t_straps(size, time(0)) {
    }

    void set(int val, int index) {
        vec[index] = val;
        t_straps[index] = time(0);
    }

    int get(int index) {
        if (t_straps[index] > g_strap)
            return vec[index];
        return g_val;
    }

    void set_all(int val) {
        g_val = val;
        g_strap = time(0);
    }
};