func_code_string: #include <bits/stdc++.h>   using namespace std;   int n, m, nxt[100010], pre[100010];   pair<int, int> b[100010];   struct Frog {     int p, a, id;   } a[100010];   set<pair<int, int> > s;   inline bool operator<(Frog a, Frog b) { return a.p < b.p; }   inline int cal(int i, int j) {     if (i == j) return 0x7fffffff;     int p1 = a[i].p, p2 = a[j].p;     if (i > j) (p2 += a[j].a) %= m;     int d = (p2 - p1 + m) % m, step = (a[i].a - a[j].a);     if (d <= a[i].a) return 1;     if (a[j].a >= a[i].a) return 0x7fffffff;     return (d - a[j].a + step - 1) / step;   }   int main() {     scanf( %d%d , &n, &m);     for (int i = 0; i < n; i++)       scanf( %d%d , &a[i].p, &a[i].a), a[i].p--, b[i] = make_pair(a[i].p, i);     sort(b, b + n);     for (int i = 0; i < n; i++) {       nxt[b[i].second] = b[(i + 1) % n].second;       pre[b[(i + 1) % n].second] = b[i].second;     }     for (int i = 0; i < n; i++) s.insert(make_pair(cal(i, nxt[i]), i));     while (!s.empty()) {       set<pair<int, int> >::iterator it = s.begin();       int i = it->second;       if (it->first == 0x7fffffff) break;       s.erase(it);       s.erase(make_pair(cal(nxt[i], nxt[nxt[i]]), nxt[i]));       s.erase(make_pair(cal(pre[i], i), pre[i]));       a[i].p += cal(i, nxt[i]);       a[i].a--;       nxt[i] = nxt[nxt[i]];       pre[nxt[i]] = i;       s.insert(make_pair(cal(pre[i], i), pre[i]));       s.insert(make_pair(cal(i, nxt[i]), i));     }     printf( %d n , s.size());     for (set<pair<int, int> >::iterator it = s.begin(); it != s.end(); it++)       printf( %d  , it->second + 1);     return 0;   }   