牛客多校第六场题解

B – Eezie and Pie

链式向前星建图 + LCA

代码

#includeusing namespace std;#define js ios::sync_with_stdio(false);cin.tie(0); cout.tie(0)#define debug system("pause")const int N = 2*1e6+5; //N点数const int M = 2*N; //M边数//Graphint n,m;//输入点数、边数int idx;//实际边数int head[N];//以i为起点的第一条边的下标struct Edge{ int to, next;}edge[M]; //to边的终点 w边的权值 next同起点下一条边的下标void add(int u, int v){edge[idx].to = v;edge[idx].next = head[u];head[u] = idx++;}int f[N]; //存答案int d[N];int vis[N];vector v;int dfs(int cur){vis[cur]=1; if(d[cur]>n; //输入点数for(int i=1;i>u>>v;add(v,u);add(u,v);}for(int i=1;i>d[i];f[i]=0;}dfs(1);for(int i=1;i<=n;i++)cout<<f[i]<<" ";}int main(){js;int T=1; while(T--) solve();debug;return 0;}

G – Icon Design

找规律 或 暴力打表(1<=n<=5)

J – Number Game

推导公式即可

代码

#include using namespace std;#define js ios::sync_with_stdio(false);cin.tie(0); cout.tie(0)#define debug system("pause")#define ll long long#define endl "\n"void solve(){ll a,b,c,x; cin>>a>>b>>c>>x;ll x1=x+c+b-a;ll x2=x+c-b;ll x3=x-c; ll u=a-2*b;if(u==0){if(x1==0) {cout<<"Yes\n"; return;}if(x2==0) {cout<<"Yes\n"; return;}if(x3==0) {cout<<"Yes\n"; return;}cout<<"No\n"; return;}else{if(x1%u==0) {cout<<"Yes\n"; return;}if(x2%u==0) {cout<<"Yes\n"; return;}if(x3%u==0) {cout<<"Yes\n"; return;}cout<>T;while(T--) solve();debug;}