#include <bits/stdc++.h> #define int long long using namespace std; const int maxn = 1000007; int a[maxn], b[maxn], n; void AnsNo() { cout << "No"; exit(0); } void AnsYes() { cout << "Yes"; exit(0); } void Change(int pos, int val) { a[pos] -= 2 * val; pos++; if(pos == n) pos = 0; a[pos] += val; } int32_t main() { auto start = chrono::steady_clock::now(); ios_base::sync_with_stdio(0); cin.tie(0); if(fopen("test.inp", "r")) freopen("test.inp", "r", stdin); cin >> n; for(int i = 0; i < n; i++) cin >> a[i] >> b[i]; while(true) { bool ok = false; for(int i = 0; i < n; i++) { if(a[i] > b[i]) { int nxt = a[i] - b[i] >> 1; if(nxt == 0 && a[i] > 1) Change(i, 1), ok = 1; if(nxt > 0) Change(i, nxt), ok = 1; } } if(!ok) break; } for(int i = 0; i < n; i++) if(a[i] != b[i]) AnsNo(); AnsYes(); auto finish = chrono::steady_clock::now(); cerr << '\n'<< chrono::duration_cast<chrono::milliseconds>(finish - start).count(); }

remittance.cpp: In function 'int32_t main()':
remittance.cpp:40:32: warning: suggest parentheses around '-' inside '>>' [-Wparentheses]
                 int nxt = a[i] - b[i] >> 1;
                           ~~~~~^~~~~~
remittance.cpp:30:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
     if(fopen("test.inp", "r")) freopen("test.inp", "r", stdin);
                                ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~