题目链接
线性基+线段树分治板子题。。
调起来有点自闭。。
#include<bits/stdc++.h> #define fi first #define se second #define pb push_back #define bit bitset<B + 1> using namespace std; const int MAXN = 501, B = 1001, SS = 4001; inline int read() { char c = getchar(); int x = 0, f = 1; while(c < '0' || c > '9') {if(c == '-') f = -1; c = getchar();} while(c >= '0' && c <= '9') x = x * 10 + c - '0', c = getchar(); return x * f; } int N, M, Q, las[SS]; struct Graph { struct Edge { int u, v; bit w; int nxt; }E[3021]; int head[MAXN], num, vis[MAXN]; Graph() { memset(head, -1, sizeof(head)); memset(vis, 0, sizeof(vis)); num = 0; } bit P[B + 1], dis[MAXN]; void insert(bit s) { for(int i = B; ~i; i--) { if(s[i]) { if(!P[i].count()) {P[i] = s; break;} s = s ^ P[i]; } } } void dfs(int x, int fa) { vis[x] = 1; for(int i = head[x]; ~i; i = E[i].nxt) { int to = E[i].v; bit w = E[i].w; if((i ^ 1) == fa) continue; if(vis[to]) insert(dis[x] ^ dis[to] ^ w); else { dis[to] = dis[x] ^ w; dfs(to, i); } } } void Query() { bit ans; ans.reset(); for(int i = B; ~i; i--) if(ans[i] ^ (P[i][i])) ans ^= P[i]; for(int i = B; ~i; i--) if(ans[i]) { for(int j = i; ~j; j--) cout << ans[j]; puts(""); return ; } puts("0"); } void AddEdge(int x, int y, bit w) { E[num] = {x, y, w, head[x]}; head[x] =num++; } void Insert(int x, int y, bit w) { insert(dis[x] ^ dis[y] ^ w); } }bg; struct Edge { int u, v; bit w; }e[SS]; vector<Edge> tag[SS]; #define ls k << 1 #define rs k << 1 | 1 void Add(int k, int l, int r, int ql, int qr, Edge v) { if(ql > qr) return ; if(ql <= l && r <= qr) {tag[k].pb(v); return ;} int mid = l + r >> 1; if(ql <= mid) Add(ls, l, mid, ql, qr, v); if(qr > mid) Add(rs, mid + 1, r, ql, qr, v); } void Down(int k, int l, int r, Graph now) { if(l > r) return ; Graph nxt = now; for(auto flag: tag[k]) nxt.Insert(flag.u, flag.v, flag.w); if(l == r) { nxt.Query(); return ; } int mid = l + r >> 1; Down(ls, l, mid, nxt); Down(rs, mid + 1, r, nxt); } signed main() { N = read(); M = read(); Q = read(); for(int i = 1; i <= M; i++) { int x = read(), y = read(); bit w; cin >> w; bg.AddEdge(x, y, w); bg.AddEdge(y, x, w); } memset(las, -1, sizeof(las)); int youducuotile = 0; for(int i = 1; i <= Q; i++) { char opt[10]; scanf("%s", opt + 1); if(opt[1] == 'A') { e[++youducuotile ].u = read(), e[youducuotile ].v = read(); cin >> e[youducuotile ].w; las[youducuotile ] = i; } else if(opt[1] == 'C' && opt[2] == 'a') { int k = read(); Add(1, 1, Q, las[k], i - 1, e[k]); las[k] = -1; } else { int k = read(); Add(1, 1, Q, las[k], i - 1, e[k]); cin >> e[k].w; las[k] = i; } } for(int i = 1; i <= Q; i++) if(~las[i]) Add(1, 1, Q, las[i], Q, e[i]); bg.dfs(1, -1); bg.Query(); if(Q) Down(1, 1, Q, bg); return 0; }