[Offer收割]编程练习赛56

A.卡片游戏

暴力

#include <bits/stdc++.h>
using namespace std;
map<int, int> mp;
set<int> S;
const int maxn = 1e5 + 10;
int A[maxn], B[maxn];

int main(){
    int N, ans = 1;
    scanf("%d", &N);
    for(int i = 1; i <= N; ++i) scanf("%d", A + i), mp[A[i]]++;
    for(int i = 1; i <= N; ++i) scanf("%d", B + i);
    for(int i = 1; i <= N + 1; ++i) if(mp.find(i) == mp.end()) S.insert(i);
    for(int i = 1; i <= N; ++i){
        mp[A[i]]--;
        if(mp[A[i]] == 0) S.insert(A[i]);
        mp[B[i]]++;
        if(mp[B[i]] == 1 && S.find(B[i]) != S.end()) S.erase(B[i]);
        ans = max(ans, *S.begin());
        mp[B[i]]--;
        if(mp[B[i]] == 0) S.insert(B[i]);
        mp[A[i]]++;
        if(mp[A[i]] == 1 && S.find(A[i]) != S.end()) S.erase(A[i]);
    }
    printf("%d
", ans);
    return 0;
}

B.宝藏坐标

暴力

#include <bits/stdc++.h>
using namespace std;

vector<string> cal(string s){
    int l = s.length();
    vector<string> ret;
    if(l == 1 && s[0] == '0' || s[0] != '0') ret.push_back(s);
    for(int i = l - 1; i > 0; --i){
        if(s[l-1] != '0' && (s[0] != '0' || i == 1)) ret.push_back(s.substr(0, i) + '.' + s.substr(i, l - i));
    }
    return ret;
}

typedef pair<string, string> pii;
vector<pii> ans;

int main(){
    char s[11];
    scanf("%s", s);
    int l = strlen(s);
    for(int i = 0; i < l - 1; ++i){
        string a = string(s).substr(0, i + 1);
        string b = string(s).substr(i + 1);
        vector<string> v1 = cal(a), v2 = cal(b);
        for(int j = v1.size() - 1; j >= 0; j--)
            for(int k = v2.size() - 1; k >= 0; k--)
                ans.push_back(pii(v1[j], v2[k]));
    }
    sort(ans.begin(), ans.end());
    for(int i = 0; i < ans.size(); ++i) cout << ans[i].first << ',' << ans[i].second << endl;
    return 0;
}

C.物品分类

启发式合并

#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e5 + 10;

set<int> ih[maxn];
set<int> :: iterator it;
int fa[maxn];
int Find(int x){
    return fa[x] == x ? x : fa[x] = Find(fa[x]);
}
void Union(int x, int y){
    x = Find(x), y = Find(y);
    if(x == y) return;
    if(ih[x].size() > ih[y].size()) swap(x, y);
    for(it = ih[x].begin(); it != ih[x].end(); ++it){
        ih[y].insert(*it);
        ih[*it].erase(x);
        ih[*it].insert(y);
    }
    fa[x] = y;
}

int main(){
    int N, M;
    scanf("%d %d", &N, &M);
    for(int i = 1; i <= N; ++i) fa[i] = i;
    for(int i = 1; i <= M; ++i) {
        char op[11];
        scanf("%s", op);
        if(op[0] == 'R'){
            int x, y, o;
            scanf("%d %d %d", &x, &y, &o);
            if(o == 1) Union(x, y);
            else {
                x = Find(x), y = Find(y);
                ih[x].insert(y), ih[y].insert(x);
            }
        }
        else {
            int x, y;
            scanf("%d %d", &x, &y);
            x = Find(x), y = Find(y);
            if(x == y) puts("1");
            else if(ih[y].find(x) != ih[y].end()) puts("2");
            else puts("3");
        }
    }
    return 0;
}

D.云的观测

线段树

#include <bits/stdc++.h>
using namespace std;
typedef long long LL;
const int maxn = 5e4 + 10;
LL a[maxn];

vector<LL> Union(vector<LL> A, vector<LL> B) {
    for (int i = 0; i <= 60; i++) {
        if(!B[i]) continue;
        for (int j = 0; j <= 60; ++j) {
            if (((B[i]) & (1LL << j)) == 0) continue;
            if (!A[j]) {
                A[j] = B[i];
                break;
            }
            else B[i] ^= A[j];
        }
    }
    return A;
}

vector<LL> T[maxn<<2], S;
inline void gather(int p)
{
    T[p] = Union(T[p<<1], T[p<<1|1]);
}
void build(int p, int l, int r)
{
    if(l < r)
    {
        int mid = (l + r) >> 1;
        build(p<<1, l, mid);
        build(p<<1|1, mid + 1, r);
        gather(p);
    }
    else{
        T[p] = vector<LL>(61, 0);
        if (a[l] == 0) return;
        for (int j = 0; j <= 60; ++j)
            if ((1LL << j) & a[l]) {
                T[p][j] = a[l];
                break;
            }
    }
}
vector<LL>query(int p, int tl, int tr, int l, int r)
{
    if(tl > tr) return vector<LL>(61, 0);
    if(tr < l || r < tl) return vector<LL>(61, 0);
    if(l <= tl && tr <= r) return T[p];
    int mid = (tl + tr) >> 1;
    return Union(query(p<<1, tl, mid, l, r), query(p<<1|1, mid+1, tr, l, r));
}

int main(){
    int N, M;
    scanf("%d %d", &N, &M);
    assert(1 <= N && N <= 50000 && M >= 0 && M <= 10000);
    for(int i = 1; i <= N; ++i) scanf("%lld", a + i), assert(a[i] <= (1LL << 60));
    build(1, 1, N);
    while(M--){
        int L, R, T;
        scanf("%d %d %d", &L, &R, &T);
        assert(1 <= L && L <= R && R <= N && T >= 0 && T <= 60);
        S = vector<LL>(61, 0);
        for(int i = 1; i <= T; ++i){
            LL x;
            scanf("%lld", &x);
            assert(x <= (1LL << 60));
            for(int j = 0; j <= 60; ++j) {
                if ((x & (1LL << j)) == 0) continue;
                if (!S[j]) {
                    S[j] = x;
                    break;
                }
                else x ^= S[j];
            }
        }
        vector<LL> tmp = Union(S, query(1, 1, N, L, R));
        LL ans = 0;
        for(int j = 0; j <= 60; ++j){
            if(tmp[j] && !S[j]) ans++;
        }
        printf("%lld
", (1LL << ans));
    }
    return 0;
}