Hello 2019 自閉記
阿新 • • 發佈：2019-01-05
A：8min才過？？？
#include<iostream> #include<cstdio> #include<cmath> #include<cstdlib> #include<cstring> #include<algorithm> using namespace std; #define int long long char getc(){char c=getchar();while ((c<'A'||c>'Z')&&(c<'a'||c>'z')&&(c<'View Code0'||c>'9')) c=getchar();return c;} int gcd(int n,int m){return m==0?n:gcd(m,n%m);} int read() { int x=0,f=1;char c=getchar(); while (c<'0'||c>'9') {if (c=='-') f=-1;c=getchar();} while (c>='0'&&c<='9') x=(x<<1)+(x<<3)+(c^48),c=getchar(); return x*f; } signed main() {/*#ifndef ONLINE_JUDGE freopen("a.in","r",stdin); freopen("a.out","w",stdout); const char LL[]="%I64d\n"; #endif*/ char a=getc(),b=getc(); for (int i=0;i<5;i++) { char x=getc(),y=getc(); if (a==x||b==y) {cout<<"YES";return 0;} } cout<<"NO";return 0; //NOTICE LONG LONG!!!!! }
B：WA了一發？？？
#include<iostream> #include<cstdio> #include<cmath> #include<cstdlib> #include<cstring> #include<algorithm> using namespace std; #define int long long #define N 20 char getc(){char c=getchar();while ((c<'A'||c>'Z')&&(c<'a'||c>'z')&&(c<'0'||c>'9')) c=getchar();return c;} int gcd(int n,int m){return m==0?n:gcd(m,n%m);} int read() { int x=0,f=1;char c=getchar(); while (c<'0'||c>'9') {if (c=='-') f=-1;c=getchar();} while (c>='0'&&c<='9') x=(x<<1)+(x<<3)+(c^48),c=getchar(); return x*f; } int n,a[N]; bool flag=0; void dfs(int k,int s) { if (flag) return; if (k>n&&s==0) {flag=1;return;} if (k>n) return; dfs(k+1,(s+a[k])%360); dfs(k+1,(s-a[k]+360)%360); } signed main() { /*#ifndef ONLINE_JUDGE freopen("a.in","r",stdin); freopen("a.out","w",stdout); const char LL[]="%I64d\n"; #endif*/ n=read(); for (int i=1;i<=n;i++) a[i]=read(); dfs(1,0); if (flag) cout<<"YES";else cout<<"NO"; return 0; //NOTICE LONG LONG!!!!! }View Code
C：多餘匹配括號去掉後設右括號個數為x，左括號個數為y，則匹配的括號序列對要求y1+y2=0 x1=0 y1+x2=0，瞎貪貪就行了。RE了一發40min才過？？？
#include<iostream> #include<cstdio> #include<cmath> #include<cstdlib> #include<cstring> #include<algorithm> #include<vector> using namespace std; #define int long long #define N 500010 char getc(){char c=getchar();while ((c<'A'||c>'Z')&&(c<'a'||c>'z')&&(c<'0'||c>'9')) c=getchar();return c;} int gcd(int n,int m){return m==0?n:gcd(m,n%m);} int read() { int x=0,f=1;char c=getchar(); while (c<'0'||c>'9') {if (c=='-') f=-1;c=getchar();} while (c>='0'&&c<='9') x=(x<<1)+(x<<3)+(c^48),c=getchar(); return x*f; } int n,ans; char s[N]; vector<int> b[N<<1]; struct data { int x,y; }a[N]; signed main() { #ifndef ONLINE_JUDGE freopen("c.in","r",stdin); freopen("c.out","w",stdout); const char LL[]="%I64d\n"; #endif n=read(); for (int i=1;i<=n;i++) { scanf("%s",s+1);int m=strlen(s+1); int cnt=0; for (int j=1;j<=m;j++) { if (s[j]=='(') cnt++;else cnt--; a[i].x=min(a[i].x,cnt); } a[i].y=cnt; b[a[i].y+N].push_back(a[i].x); } // y1+y2=0 y1+x2>=0 for (int i=0;i<(N<<1);i++) sort(b[i].begin(),b[i].end()); int cnt=0; for (int i=0;i<b[N].size();i++) if (b[N][i]>=0) cnt++; ans=cnt/2; for (int i=N+1;i<(N<<1);i++) { int head=0,tail=b[i].size();tail--; while (head<b[N-(i-N)].size()&&tail>=0&&b[i][tail]>=0) { while (head<b[N-(i-N)].size()&&i-N+b[N-(i-N)][head]<0) head++; if (head>=b[N-(i-N)].size()) break; tail--;head++;ans++; } } cout<<ans; return 0; //NOTICE LONG LONG!!!!! }View Code
D：暴力dp，對每個質因子做即可。看錯題了一發？？？
#include<iostream> #include<cstdio> #include<cmath> #include<cstdlib> #include<cstring> #include<algorithm> using namespace std; #define ll long long #define P 1000000007 char getc(){char c=getchar();while ((c<'A'||c>'Z')&&(c<'a'||c>'z')&&(c<'0'||c>'9')) c=getchar();return c;} int gcd(int n,int m){return m==0?n:gcd(m,n%m);} int read() { int x=0,f=1;char c=getchar(); while (c<'0'||c>'9') {if (c=='-') f=-1;c=getchar();} while (c>='0'&&c<='9') x=(x<<1)+(x<<3)+(c^48),c=getchar(); return x*f; } ll n,prime[100]; int m,cnt[100],a[100],f[100][100],g[10010][100],inv[110],t,tot=1,ans=0; int ksm(int a,int k) { int s=1; for (;k;k>>=1,a=1ll*a*a%P) if (k&1) s=1ll*s*a%P; return s; } void dfs(int k,ll s,ll u) { if (k>t) {ans=(ans+s%P*u)%P;return;} for (a[k]=0;a[k]<=cnt[k];a[k]++) { dfs(k+1,s,u*f[k][a[k]]%P); s*=prime[k]; } } signed main() { #ifndef ONLINE_JUDGE freopen("d.in","r",stdin); freopen("d.out","w",stdout); const char LL[]="%I64d\n"; #endif cin>>n>>m; for (int i=2;1ll*i*i<=n;i++) if (n%i==0) { t++;prime[t]=i; while (n%i==0) cnt[t]++,n/=i; } if (n>1) prime[++t]=n,cnt[t]=1; for (int i=1;i<=100;i++) inv[i]=ksm(i,P-2); for (int i=1;i<=t;i++) { memset(g[0],0,sizeof(g[0]));g[0][cnt[i]]=1; for (int j=1;j<=m;j++) { g[j][cnt[i]+1]=0; for (int k=cnt[i];k>=0;k--) g[j][k]=(g[j][k+1]+1ll*g[j-1][k]*inv[k+1])%P; } for (int k=0;k<=cnt[i];k++) f[i][k]=g[m][k]; } //for (int i=1;i<=t;i++) tot=1ll*tot*C[cnt[i]+m][cnt[i]]%P;tot=inv(tot); dfs(1,1,1); //cout<<1ll*ans*tot%P; cout<<ans; return 0; //NOTICE LONG LONG!!!!! }View Code
F感覺非常神仙？？？過了很長時間才明白不是什麼亂七八糟的線段樹合併而是bitset啊？？？但還是不會啊？？？怎麼這麼多人過啊？？？叉人還被搶啊？？？自閉了啊？？？
result：rank 422 rating +12