#include <bits/stdc++.h> #include <ext/pb_ds/tree_policy.hpp> #include <ext/pb_ds/assoc_container.hpp> using namespace std; using namespace __gnu_pbds; #pragma GCC optimize("Ofast,unroll-loops,inline-functions,no-stack-protector,03") #pragma GCC target ("sse,sse2,sse3,ssse3,sse4,popcnt,abm,avx2,mmx,fma,avx,tune=native") #pragma clang loop vectorize(enable) #pragma clang loop interleave(enable) #define int long long #define sz(x) (int)x.size() #define F first #define S second #define pb push_back #define nl '\n' #define o_set tree<int, null_type, less_equal<int>, rb_tree_tag, tree_order_statistics_node_update> mt19937 rng(chrono::steady_clock::now().time_since_epoch().count()); typedef pair<int, int> pii; void file( string s = "" ) { if( s.empty() ) return; freopen((s + ".in").c_str(), "r", stdin); freopen((s + ".out").c_str(), "w", stdout); } const int N = 5e5 + 2; const int N1 = 1e6 + 2; const int inf = 1e9 + 2; const int INF = 1e18 + 2; const int mod = 1e9 + 7; const double eps = 1e-9; int T = 1, n, x[N], e[N]; pii seg[N]; void solve() { cin >>n; for( int i = 1; i <= n; ++i ) { cin >>x[i] >>e[i]; seg[i] = {e[i] - x[i], e[i] + x[i]}; } sort(seg + 1, seg + n + 1); vector< pii > v; for( int i = 1; i <= n; ++i ) { while( !v.empty() && v.back().S <= seg[i].S ) v.pop_back(); v.pb(seg[i]); } cout <<sz(v); } signed main() { file(""); ios_base::sync_with_stdio(false); cin.tie(nullptr); // cin >>T; while( T-- ) solve(); }

Main.cpp: In function 'void file(std::string)':
Main.cpp:27:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   27 |     freopen((s + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:28:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   28 |     freopen((s + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~