标签:substr 统计 href string event for -418 排序 char
A数学题统计
#include<iostream> #include<cstdio> #include<cstring> #include<algorithm> #define mod 1000000007 long long m,n; long long sum; int main() { scanf("%lld%lld",&m,&n); long long int a,b; a=2*(m+n-2); b=(2*m*n-3*m-3*n+4); sum=((a%mod)*(b%mod))%mod; printf("%lld\n",sum ); return 0; }
B数学期望
#include<iostream> #include<cstdio> #include<cstring> #include<algorithm> using namespace std; int n,x,a,b; int main() { scanf("%d%d%d%d",&n,&x,&a,&b); int aa,bb; aa=n*a; bb=n*b; double ans; ans=aa*x+bb*(100-x); ans=ans/100.; printf("%.2lf",ans); return 0; }
D水题排序
#include<iostream> #include<cstdio> #include<cstring> #include<algorithm> #define N 100009 using namespace std; int n; int a[N]; int main() { scanf("%d",&n); for(int i=1;i<n;i++) scanf("%d",&a[i]); sort(a+1,a+n);a[n]=n+1; for(int i=1;i<=n;i++) { if(i!=a[i]) { cout<<i; break; } } return 0; }
E数学题根号n求因子个数
#include<iostream> #include<cstdio> #include<cstring> #include<algorithm> using namespace std; int get_num(long long n){ int tot=1; for(int i=2;i*i<=n;++i){ if(n%i==0){ int x=0; while(n%i==0){ n/=i; x++; } tot*=(x+1); } } if(n>1)tot*=2; return tot; } int main(){ long long n; cin>>n; int ans=0; while(n!=2) { n=get_num(n);//求n的因子个数 ans++; } cout<<ans; return 0; }
F图论题dfs求每个黑点对答案的贡献
#include<iostream> #include<cstdio> #include<cstring> #include<algorithm> #define N 100009 #define LL long long using namespace std; int n; LL cnt,ans; int sumedge; int head[N],vis[N]; char col[N]; struct Edge { int x,y,nxt; Edge(int x=0,int y=0,int nxt=0): x(x),y(y),nxt(nxt){} }edge[N<<1]; void add(int x,int y) { edge[++sumedge]=Edge(x,y,head[x]); head[x]=sumedge; } void dfs(int x) { for(int i=head[x];i;i=edge[i].nxt) { int v=edge[i].y; if(col[v]==‘B‘||vis[v]) continue; vis[v]=true;cnt++; dfs(v); } } void slove() { for(int k=1;k<=n;k++) { if(col[k]==‘W‘) continue; int x=k; LL tot=0; memset(vis,0,sizeof(vis)); for(int i=head[x];i;i=edge[i].nxt) { int v=edge[i].y; if(col[v]==‘W‘) { cnt=1; vis[v]=true; dfs(v); ans=ans+tot*cnt+cnt; tot=tot+cnt; } } } cout<<ans<<endl; } int main() { scanf("%d",&n); scanf("%s",col+1); for(int i=1;i<n;i++) { int x,y; scanf("%d%d",&x,&y); add(x,y); add(y,x); } slove(); return 0; }
G字符串题妙啊妙
#include<iostream> #include<cstdio> #include<cstring> #include<algorithm> #define N 200009 using namespace std; int n,k,ans; char s[N]; int cnt[30]; int pos[30][N]; int main() { scanf("%d%d",&n,&k); scanf("%s",s+1); ans=n+1; for(int i=1;i<=n;i++) { int x=s[i]-‘a‘+1; cnt[x]++; pos[x][cnt[x]]=i; } for(int i=1;i<=26;i++) { if(cnt[i]<k) continue; for(int j=1;j<=cnt[i]-k+1;j++) { ans=min(ans,pos[i][j+k-1]-pos[i][j]+1); } } if(ans==n+1) cout<<"-1\n"; else cout<<ans<<endl; return 0; }
H二分+贪心
#include<iostream> #include<cstdio> #include<cstring> #include<algorithm> #define N 200009 using namespace std; int n,k; int l,r,mid,ans; int sum[N]; char s[N]; bool check(int x) { for(int i=0;i<=n-x;i++) { if(x-(sum[i+x]-sum[i])<=k)return true; if(sum[i+x]-sum[i]<=k) return true; } return false; } int main() { scanf("%d%d",&n,&k); scanf("%s",s+1); for(int i=1;i<=n;i++) { sum[i]=sum[i-1]+s[i]-‘0‘; } l=1;r=n; while(l<=r) { mid=(l+r)>>1; if(check(mid)) { ans=mid; l=mid+1; }else r=mid-1; } cout<<ans<<endl; return 0; }
I字符串区间dp妙啊妙
#include<iostream> #include<cstdio> #include<cstring> #include<algorithm> #define N 300009 #define LL long long using namespace std; int n,a,b,c; string s; LL dp[N]; int main() { scanf("%d%d%d%d",&n,&a,&b,&c); cin>>s; for(int i=0;i<n;i++) { if(i)dp[i]=max(dp[i],dp[i-1]); if(i+3<n&&s.substr(i,4)=="nico") dp[i+3]=max(dp[i+3],dp[i]+a); if(i+5<n&&s.substr(i,6)=="niconi") dp[i+5]=max(dp[i+5],dp[i]+b); if(i+9<n&&s.substr(i,10)=="niconiconi")dp[i+9]=max(dp[i+9],dp[i]+c); } cout<<dp[n-1]; return 0; }
标签:substr 统计 href string event for -418 排序 char
原文地址:https://www.cnblogs.com/zzyh/p/12267027.html