2024牛客寒假算法基础集训营4（视频讲解题目）
- 视频链接
- A
- B
- C
- D
- E
- F
- G、H（下面是hard版本的代码两个都可以过）
视频链接
2024牛客寒假算法基础集训营4（视频讲解题目）
A
#include<bits/stdc++.h>
#define endl '\n'
#define deb(x) cout << #x << " = " << x << '\n';
#define INF 0x3f3f3f3f
using namespace std;
void solve()
{
int a, b ,k;
cin >> a >> b >> k;
if(a >= k * b){
cout << "good" << endl;
}else{
cout << "bad" << endl;
}
}
signed main()
{
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int t;
t = 1;
//cin >> t;
while(t--)
solve();
}
B
#include<bits/stdc++.h>
#define endl '\n'
#define deb(x) cout << #x << " = " << x << '\n';
#define INF 0x3f3f3f3f
using namespace std;
void solve()
{
int n; cin >> n;
vector<int>a(n);
int x = 0;
for(int i = 0; i < n; i ++){
cin >> a[i];
x += (a[i] - 1);
}
if(x % 2){
cout << "gui" << endl;
}else{
cout << "sweet" << endl;
}
}
signed main()
{
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int t;
t = 1;
// cin >> t;
while(t--)
solve();
}
C
#include<bits/stdc++.h>
#define endl '\n'
#define deb(x) cout << #x << " = " << x << '\n';
#define INF 0x3f3f3f3f
using namespace std;
typedef pair<int,int> pii;
void solve()
{
int n, m, x, y;
cin >> n >> m >> x >> y;
x -- ,y --;
vector<string> g(n + 10);
for(int i = 0; i < n; i ++){
cin >> g[i];
}
int p, q; cin >> p >> q;
vector<pii>ops(q);
for(int i = 0; i < q; i ++){
cin >> ops[i].first >> ops[i].second;
}
while(p--){
for(int j = 0; j < q; j ++){
int op = ops[j].first, z = ops[j].second - 1;
if(op == 1){
char s = g[z][m - 1];
for(int i = m - 1; i >= 1; i --){
g[z][i] = g[z][i - 1];
}
g[z][0] = s;
}else{
char s = g[n - 1][z];
for(int i = n - 1; i >= 1; i --){
g[i][z] = g[i - 1][z];
}
g[0][z] = s;
}
}
}
cout << g[x][y] << endl;
}
signed main()
{
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int t;
t = 1;
// cin >> t;
while(t--)
solve();
}
D
#include<bits/stdc++.h>
#define endl '\n'
#define deb(x) cout << #x << " = " << x << '\n';
#define INF 0x3f3f3f3f
#define int long long
using namespace std;
void solve()
{
int n; cin >> n;
vector<int>a(n);
for(int i = 0; i < n; i ++){
cin >> a[i];
}
if(n == 1){
cout << 1 << endl;
return;
}
int s = 0;
for(int i = 0; i < n; i ++){
s += a[i];
}
int ans = 0;
for(int i = 1; i <= s / i; i ++){
if(s % i){
continue;
}
int a = i, b = s / i;
if(s / a >= n){
ans ++;
}
if(a != b and s / b >= n){
ans ++;
}
}
cout << ans << endl;
}
signed main()
{
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int t;
t = 1;
//cin >> t;
while(t--)
solve();
}
E
#include<bits/stdc++.h>
#define endl '\n'
#define deb(x) cout << #x << " = " << x << '\n';
#define INF 0x3f3f3f3f
#define int long long
using namespace std;
void solve()
{
int n, k; cin >> n >> k;
vector<int>a(n + 1), s(n + 1);
for(int i = 1; i <= n; i ++){
cin >> a[i];
s[i] = s[i - 1] + a[i];
}
int ans = 0;
map<int,int>st;
st[0] = 1;
for(int i = 1; i <= n; i ++){
int p = s[i] % k;
if(st[p]){
ans += st[p];
st.clear();
}
st[p] ++;
}
cout << ans << endl;
}
signed main()
{
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int t;
t = 1;
//cin >> t;
while(t--)
solve();
}
F
#include<bits/stdc++.h>
#define endl '\n'
#define deb(x) cout << #x << " = " << x << '\n';
#define INF 0x3f3f3f3f3f3f3f3f
#define int long long
using namespace std;
const int N = 1e3 + 10;
int a[N];
int f[N][10], g[N][10], dp[N];
int has[N][N][2];
int cal(int x, int y){
if(y - x + 1 < 6){
return 0;
}
if(has[x][y - 1][0] != INF and has[x][y - 1][1] != INF){
int res = max(has[x][y - 1][1], has[x][y - 1][0] - a[y]);
return res;
}
for(int i = x; i <= y + 1; i ++){
for(int j = 0; j <= 6; j ++){
f[i][j] = -INF;
g[i][j] = INF;
}
}
for(int i = x; i <= y; i ++){
if(i != x)
{
f[i][1] = max(f[i - 1][1], a[i]);
g[i][1] = min(g[i - 1][1], a[i]);
}
else
{
f[i][1] = a[i];
g[i][1] = a[i];
}
if(i - x + 1 >= 2)
{
g[i][2] = min(g[i - 1][2], g[i - 1][1] - a[i]);
f[i][2] = max(f[i - 1][2], f[i - 1][1] - a[i]);
}
else
continue;
if(i - x + 1 >= 3){
if(g[i - 1][2] != INF){
f[i][3] = max(f[i - 1][3], max(g[i - 1][2] * a[i], f[i - 1][2] * a[i]));
}else{
f[i][3] = max(f[i - 1][3], f[i - 1][2] * a[i]);
}
if(f[i - 1][2] != -INF)
g[i][3] = min(g[i - 1][3], min(g[i - 1][2] * a[i], f[i - 1][2] * a[i]));
else
g[i][3] = min(g[i - 1][3], g[i - 1][2] * a[i]);
}else
continue;
if(i - x + 1 >= 4)
{
f[i][4] = max(f[i - 1][4], f[i - 1][3] - a[i]);
g[i][4] = min(g[i - 1][4], g[i - 1][3] - a[i]);
}
else
continue;
if(i - x + 1 >= 5){
if(g[i - 1][4] != INF)
f[i][5] = max(f[i - 1][5], max(g[i - 1][4] * a[i], f[i - 1][4] * a[i]));
else
f[i][5] = max(f[i - 1][5], f[i - 1][4] * a[i]);
if(f[i - 1][4] != -INF)
g[i][5] = min(g[i - 1][5], min(g[i - 1][4] * a[i], f[i - 1][4] * a[i]));
else
g[i][5] = min(g[i - 1][5], g[i - 1][4] * a[i]);
}else
continue;
if(i - x + 1 >= 6)
f[i][6] = max(f[i - 1][6], f[i - 1][5] - a[i]);
}
int res = 0;
int xx = 0;
for(int i = x; i <= y; i ++){
res = max(res, f[i][6]);
xx = max(xx, f[i][5]);
}
has[x][y][1] = res;//选6个数字的最大值
has[x][y][0] = xx;//选5个数字的最大值
return res;
}
void solve()
{
int n; scanf("%lld", & n);
for(int i = 1; i <= n; i ++){
scanf("%lld", a + i);
}
for(int i = 1; i <= n; i ++){
for(int j = 1; j <= n; j ++){
has[i][j][0] = has[i][j][1] = INF;
}
}
for(int i = 1; i <= n; i ++){
dp[i] = dp[i - 1];
for(int j = 1; j <= i; j ++){
dp[i] = max(dp[i], dp[j - 1] + cal(j, i));
}
}
printf("%lld", dp[n]);
}
signed main()
{
int t = 1;
while(t--)
solve();
}
G、H（下面是hard版本的代码两个都可以过）
#include<bits/stdc++.h>
#define endl '\n'
#define deb(x) cout << #x << " = " << x << '\n';
#define INF 0x3f3f3f3f
using namespace std;
const int N = 3e3 + 10;
char g[N][N];
int ul[N][N], ur[N][N], ls[N][N], rs[N][N];
class BIT{
private:
vector<long long>tre;
int n;
public:
BIT(int size): n(size), tre(size + 1, 0) {};
public:
int lowbit(int x){
return x & -x;
}
void add(int pos, long long x){
for(int i = pos; i <= n; i += lowbit(i))
tre[i] = tre[i] + x;
}
long long sum(int pos){
long long res = 0;
for(int i = pos; i; i -= lowbit(i))
res = res + tre[i];
return res;
}
};
void solve()
{
int n, m; cin >> n >> m;
for(int i = 1; i <= n; i ++){
string s; cin >> s;
for(int j = 1; j <= m; j ++){
g[i][j] = s[j - 1];
}
}
for(int i = n; i >= 1; i --){
for(int j = 1; j <= m; j ++){
if(g[i][j] == '*'){
ul[i][j] = ul[i + 1][j - 1] + 1;
ur[i][j] = ur[i + 1][j + 1] + 1;
ls[i][j] = ls[i][j - 1] + 1;
}else{
ul[i][j] = ur[i][j] = ls[i][j] = 0;
}
}
for(int j = m; j >= 1; j --){
if(g[i][j] == '*'){
rs[i][j] = rs[i][j + 1] + 1;
}else{
rs[i][j] = 0;
}
}
}
long long ans = 0;
for(int j = 1; j <= m; j ++){
BIT t(n);//记录合法点的个数
vector<vector<int>>del(n + 1);//记录在v这个点需要删除的点。
for(int i = n; i >= 1; i --){
if(g[i][j] == '*'){
int v = i - min(ls[i][j], rs[i][j]) + 1;
if(v >= 1){
del[v].push_back(i);
}
int low = i + min(ul[i][j], ur[i][j]) - 1;
ans += t.sum(low);
t.add(i, 1);
}
for(auto x: del[i]){
t.add(x, -1);
}
}
}
cout << ans << endl;
}
signed main()
{
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int t;
t = 1;
// cin >> t;
while(t--)
solve();
}
