//finding closest element int closest(vector<int> &s1, int x) { int dif = INT_MAX; auto j = lower_bound(s1.begin(), s1.end(), x); if(j == s1.end()) dif = min(dif, abs(*(–j) – x)); else if(j == s1.begin()) dif = min(dif, abs(*j – x)); else { dif = min(dif, abs(*j – x)); dif = min(dif, abs(*(–j) – x)); } return dif; […]