// compile: make data // run: ./data < data.in #include <bits/stdc++.h> using namespace std; #pragma GCC optimize("O3,unroll-loops") #pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt") #ifdef LOCAL #include <debug/codeforces.h> #define debug(x...) _debug_print(#x, x); #define Debug(x...) _debug_print_format(#x, x); std::ifstream terminal("/dev/tty"); #define PP cerr<<"\033[1;30mpause...\e[0m",terminal.ignore(); #else #define debug(x...) #define Debug(x...) #define PP #endif template<typename...Args> void print_(Args...args){((cout<<args<<" "),...)<<endl;} #define rep(i,a,b) for(int i=(a);i<(int)(b);++i) #define sz(v) ((int)(v).size()) #define print(...) print_(__VA_ARGS__); #define FIND(a, x) ((find(a.begin(),a.end(),(x))!=a.end())?1:0) #define cmin(x,...) x=min({(x),__VA_ARGS__}) #define cmax(x,...) x=max({(x),__VA_ARGS__}) #define INTMAX (int)(9223372036854775807) // #define INF (int)(1152921504606846976) #define NaN (int)(0x8b88e1d0595d51d1) #define double long double #define int long long #define uint unsigned long long #define MAXN 200010 template <class T> struct treap { struct node { node *ch[2]; int rd, size; T val; }; node *root = nullptr; vector<node> pool; treap(int N) { pool.resize(N); } int total = 0; node *newnode(T val) { node *x = &pool[total++]; x->val = val; x->rd = rand(); x->size = 1; return x; } int getsize(node *x) {return x ? x->size : 0; } void pushup(node *x) { if (!x) return; x->size = getsize(x->ch[0]) + getsize(x->ch[1]) + 1; } void pushdown(node *x) { if (x) return; } pair<node*, node*> split(node *x, int size) { if (!x) return {nullptr, nullptr}; pushdown(x); if (size <= getsize(x->ch[0])) { auto [lc, rc] = split(x->ch[0], size); x->ch[0] = rc; pushup(x); return {lc, x}; } auto [lc, rc] = split(x->ch[1], size - getsize(x->ch[0]) - 1); x->ch[1] = lc; pushup(x); return {x, rc}; } node *merge(node *x, node *y) { if (!x && !y) return nullptr; if (!x) return y; if (!y) return x; pushdown(x), pushdown(y); if (x->rd < y->rd) { x->ch[1] = merge(x->ch[1], y); pushup(x); return x; } y->ch[0] = merge(x, y->ch[0]); pushup(y); return y; } void insert(T val, int rank) { auto [l, r] = split(root, rank); node *mid = merge(l, newnode(val)); root = merge(mid, r); } vector<T> inorder() { vector<T> res; stack<node*> st; for (node *x = root; x || sz(st); ) { if (x) st.push(x), x = x->ch[0]; else { x = st.top(); st.pop(); res.push_back(x->val); x = x->ch[1]; } } return res; } tuple<node*, node*, node*> interval(int l, int r) { auto [L, y] = split(root, r+1); auto [x, mid] = split(L, l); return {x, mid, y}; } void graphviz_dump(string filename = "graph.dot") { FILE *f = fopen(filename.c_str(), "w"); fprintf(f, "digraph {\n"); rep(i, 0, total) { node *x = &pool[i]; fprintf(f, "%lld.c_str()); rep(j, 1, sz(desired)) fprintf(f, " | %s", desired[j].c_str()); fprintf(f, "\" shape=\"record\"];\n"); } rep(i, 0, total) { node *x = &pool[i]; if (x->ch[0]) fprintf(f, " %lld -> %ld;\n", i, x->ch[0] - &pool[0]); if (x->ch[1]) fprintf(f, " %lld -> %ld;\n", i, x->ch[1] - &pool[0]); } fprintf(f, "}\n"); } void solve(int l, int r) { auto [x, mid, y] = interval(l, r); root = merge(merge(x, y), mid); } }; // struct value { // int c; // }; int32_t main() { ios::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr); int n, q; cin >> n >> q; string s; cin >> s; struct value { int c; }; treap<value> t(sz(s)); rep(i, 0, sz(s)) t.insert({s[i]}, i); while (q--) { int l, r; cin >> l >> r; --l, --r; t.solve(l, r); } auto v = t.inorder(); rep(i, 0, sz(v)) cout << (char)v[i].c; cout << endl; // t.graphviz_dump(); return 0; }
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