CCF CSP 第十九次认证
机器学习派上了用场
#include<bits/stdc++.h>
using namespace std;
int getsign(long long x){
return x<0?-1:1;
}
int main(int argc, char const *argv[])
{
int n;
int t;
cin>>n>>t;
map<char, vector<pair<long long,long long>>> p;
int x,y;
char c;
for(int i=0; i<n; i++){
cin>>x>>y>>c;
p[c].push_back(make_pair(x,y));
}
while(t--){
long long a1,a2,a3;
cin>>a1>>a2>>a3;
long long A = a1+p['A'][0].first*a2+p['A'][0].second*a3;
long long B = a1+p['B'][0].first*a2+p['B'][0].second*a3;
if(getsign(A)==getsign(B)){
cout<<"No"<<endl;
continue;
}
bool flag = false;
for(auto pp:p['A']){
long long temp = a1+pp.first*a2+pp.second*a3;
if(getsign(temp)*getsign(A)<0){
flag = true;
break;
}
}
for(auto pp:p['B']){
long long temp = a1+pp.first*a2+pp.second*a3;
if(getsign(temp)*getsign(B)<0){
flag = true;
break;
}
}
if(flag)
cout<<"No"<<endl;
else
cout<<"Yes"<<endl;
}
return 0;
}
双指针
#include<bits/stdc++.h>
using namespace std;
int main(int argc, char const *argv[])
{
ios::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
int n;
cin>>n;
int a, b;
cin>>a>>b;
vector<pair<long long,long long>> X(a),Y(b);
long long ans = 0;
long long x,y;
for (int i = 0; i < a; ++i)
{
cin>>x>>y;
X[i] = make_pair(x,y);
}
for (int i = 0; i < b; ++i)
{
cin>>x>>y;
Y[i] = make_pair(x,y);
}
sort(X.begin(), X.end());
sort(Y.begin(), Y.end());
int i=0,j=0;
while(i<a&&j<b){
if(X[i].first==Y[j].first)
ans += X[i++].second* Y[j++].second;
else if(X[i].first<Y[j].first)
i++;
else
j++;
}
cout<<ans<<endl;
return 0;
}
阅读理解题，后面太麻烦了
先骗四十分
#include<bits/stdc++.h>
using namespace std;
string gets1(string s){
string res = "";
int l = 0;
int r = s.length()-1;
while(l<=r&&s[l]==' ') l++;
while(l<=r&&s[r]==' ') r--;
while(l<=r)
res += s[l++];
return res;
}
int main(int argc, char const *argv[])
{
string s;
int n;
// freopen("test.dat","r", stdin);
cin>>n;
// getchar();
int ans = 0;
int state = 0;
string temp = "";
int len = 0;
while(getline(cin,s)){
// cout<<s;
string res = gets1(s);
if(res.length()==0){ //遇到了一个新的段落
if(state==0)
continue;
for(int i=0; i<temp.length(); i++){
if(len%n==0&&temp[i]==' ')
continue;
else{
len++;
}
}
// cout<<len<<endl;
ans += len/n + ((len%n)>0)+1;
temp = "";
len = 0;
state = 0;
// cout<<ans<<endl;
}else{
temp+= " "+res;
state = 1;
}
}
// cout<<len<<endl;ans += len/n + ((len%n)>0)+1;
if(temp.length()){
// if(len%n!=0)
// cout<<endl;
for(int i=0; i<temp.length(); i++){
if(len%n==0&&temp[i]==' ')
continue;
else{
len++;
}
}
ans += len/n + ((len%n)>0)+1;
}
cout<<ans-1<<endl;
return 0;
}
// 段落： 去掉每行首位的连续空格
// 每行开头如果是空格，那么要去掉空格
// 如果有多行， 则将各行用一个空格链接起来
// 段落与段落之间或者段落与空行之间应该空出一行间距
// 项目：
//
矩阵快速幂
能过96分，第一次接触矩阵快速幂
判重需要仔细考虑，两个的时候只能考虑单个数字生成
和相邻数字生成的新的对
#include<bits/stdc++.h>
using namespace std;
const long long mod = 998244353;
vector<vector<long long>> se={
{0,0,1,0,0,0,0,0,0,0,0,0,0,0},
{1,0,0,0,0,0,0,0,0,0,0,0,0,0},
{0,1,0,1,0,0,0,0,0,0,0,0,0,0},
{0,0,1,1,0,0,0,0,0,0,0,0,0,0},
{0,0,1,0,0,0,0,0,0,0,0,0,0,0},
{0,0,0,0,1,0,0,0,0,0,0,0,0,0},
{0,0,0,0,0,0,0,0,0,0,0,1,0,0},
{0,0,0,0,0,0,0,0,0,0,1,0,0,0},
{0,0,0,0,0,1,0,0,0,0,0,0,1,0},
{0,0,0,0,0,0,0,1,0,0,0,0,0,0},
{0,0,0,0,0,0,1,0,0,0,0,0,0,0},
{0,0,0,1,0,0,0,0,0,0,0,0,0,1},
{0,0,0,0,0,0,0,0,1,0,0,0,0,0},
{0,0,0,0,0,0,0,0,0,1,0,0,0,0}
};
// vector<vector<long long>> seini = {{1,0,0,0,0,0,0,0,0,0,0,0,0,0}};
vector<long long> fi = {1,2,4,6,16,26,41,44,46,61,62,64,66,42};
vector<vector<long long>> mmul(vector<vector<long long >> a, vector<vector<long long>> b){
int n = a.size();
int m = a[0].size();
int mm = b[0].size();
vector<vector<long long>> aa(n, vector<long long>(mm, 0LL));
for(int i=0; i<n; i++){
for(int j=0; j<mm;j++){
for(int k=0; k<m; k++){
aa[i][j] = ((aa[i][j]%mod)+((a[i][k]%mod)*(b[k][j]%mod))%mod)%mod;
}
}
}
return aa;
}
vector<vector<long long>> matrix_mul(vector<vector<long long>> a, int t){
vector<vector<long long>> res(14, vector<long long>(14, 0LL));
for(int i=0; i<14; i++){
for(int j=0; j<14; j++){
res[i][j]=0;
if(i==j)
res[i][j]=1LL;
}
}
while(t){
if(t&1){
res = mmul(a,res);
}
a = mmul(a,a);
t = t>>1;
}
return res;
}
int main()
{
int n;
cin>>n;
string s;
cin>>s;
int targ = stoi(s);
se = matrix_mul(se, n);
for(int i=0; i<14; i++){
if(fi[i]==targ){
cout<<se[i][0]<<endl;
return 0;
}
}
cout<<0<<endl;
return 0;
}
只会dfs暴力前四十分，但是不知道为啥只能过三十分
离谱了，想了一天也没看出来哪里错了，随缘了
#include<bits/stdc++.h>
#define LL long long
using namespace std;
// 0表示不选
// 1表示选边界
// 2表示不选边界
vector<vector<LL>> a(1100, vector<LL>(5,0));
LL n, m;
LL used[1100];
LL buy[1100];
LL ans = 0;
vector<pair<LL,pair<LL, LL>>> sss;
bool judge(){
for(auto ss:sss){
if(ss.second.second==1){
if(used[ss.first]&&!used[ss.second.first])
return false;
}else{
if(used[ss.first]==1&&!used[ss.second.first])
return false;
}
}
return true;
}
LL cal(){
LL res = 0;
for(LL i=1; i<=n; i++){
res += buy[i];
}
return res;
}
LL cal_2(LL i, LL x){
return a[i][2]*x*x+a[i][3]*x+a[i][4];
}
void dfs(LL i){
if(i==n+1){
if(judge())
ans = max(ans, cal());
// cout<<endl<<cal()<<endl;
return;
}
for(LL t=0; t<3; t++){
used[i]=t;
buy[i]=0;
if(t==1){
buy[i] = max(cal_2(i,a[i][0]), cal_2(i,a[i][1]));
}
else if(t==2){
if(a[t][2]==0){
buy[i]=max(cal_2(i,a[i][0]+1), cal_2(i,a[i][1]-1));
}else{
buy[i]=max(cal_2(i,a[i][0]+1), cal_2(i,a[i][1]-1));
LL temp = (-a[i][1]/(2LL*a[i][0]));
if(temp>a[i][0]&&temp<a[i][1])
buy[i] = max(buy[i], cal_2(i, temp));
temp -= 1;
if(temp>a[i][0]&&temp<a[i][1])
buy[i] = max(buy[i], cal_2(i, temp));
temp += 2;
if(temp>a[i][0]&&temp<a[i][1])
buy[i] = max(buy[i], cal_2(i, temp));
}
}
dfs(i+1);
}
}
int main()
{
ans = 0;
memset(used,0,sizeof used);
memset(buy,0,sizeof buy);
cin>>n>>m;
for(LL i=1; i<=n; i++){
cin>>a[i][0]>>a[i][1]>>a[i][2]>>a[i][3]>>a[i][4];
}
LL x,y,c;
for(LL i=0; i<m; i++){
cin>>c>>x>>y;
sss.push_back(make_pair(x,make_pair(y,c)));
}
dfs(1);
cout<<ans<<endl;
return 0;
}
离谱的，不知道九月考试能考多少分
一条有梦想的咸鱼
