离散化+并查集
set比unique慢好多
unique
1 #include<cstdio> 2 #include<cstring> 3 #include<cmath> 4 #include<ctime> 5 #include<cstdlib> 6 #include<iostream> 7 #include<algorithm> 8 #include<set> 9 #define clr(a,x) memset(a,x,sizeof(a)) 10 #define rep(i,l,r) for(int i=l;i<r;i++) 11 using namespace std; 12 int read() 13 { 14 char c=getchar(); 15 int ans=0,f=1; 16 while(!isdigit(c)){ 17 if(c=='-') f=-1; 18 c=getchar(); 19 } 20 while(isdigit(c)){ 21 ans=ans*10+c-'0'; 22 c=getchar(); 23 } 24 return ans*f; 25 } 26 const int maxn=200005; 27 int f[maxn],a[maxn][3],b[maxn][2],c[maxn]; 28 int find(int a) 29 { 30 return (f[a]==a?f[a]:f[a]=find(f[a])); 31 } 32 int main() 33 { 34 freopen("prog10.in","r",stdin); 35 freopen("prog10.out","w",stdout); 36 int t=read(); 37 while(t--){ 38 int n=read(),cnt=0,cnt1=0; 39 bool flag=1; 40 clr(a,0),clr(b,0),clr(c,0); 41 rep(i,0,maxn) f[i]=i; 42 rep(i,0,n){ 43 a[i][0]=read(); 44 a[i][1]=read(); 45 a[i][2]=read(); 46 if(!a[i][2]){ 47 b[cnt][0]=a[i][0]; 48 b[cnt++][1]=a[i][1]; 49 } 50 c[cnt1++]=a[i][0]; 51 c[cnt1++]=a[i][1]; 52 } 53 cnt1=unique(c,c+(n<<1))-c; 54 sort(c,c+cnt1); 55 rep(i,0,n){ 56 if(a[i][2]==1){ 57 f[find(lower_bound(c,c+cnt1,a[i][0])-c)]=find(lower_bound(c,c+cnt1,a[i][1])-c); 58 } 59 } 60 rep(i,0,cnt){ 61 if(find(lower_bound(c,c+cnt1,b[i][0])-c)==find(lower_bound(c,c+cnt1,b[i][1])-c)){ 62 flag=0;break; 63 } 64 } 65 if(flag) printf("YES "); 66 else printf("NO "); 67 } 68 return 0; 69 }
set
1 #include<cstdio> 2 #include<cstring> 3 #include<cmath> 4 #include<ctime> 5 #include<cstdlib> 6 #include<iostream> 7 #include<algorithm> 8 #include<set> 9 #define clr(a,x) memset(a,x,sizeof(a)) 10 #define rep(i,l,r) for(int i=l;i<r;i++) 11 using namespace std; 12 int read() 13 { 14 char c=getchar(); 15 int ans=0,f=1; 16 while(!isdigit(c)){ 17 if(c=='-') f=-1; 18 c=getchar(); 19 } 20 while(isdigit(c)){ 21 ans=ans*10+c-'0'; 22 c=getchar(); 23 } 24 return ans*f; 25 } 26 set<int>S; 27 const int maxn=200005; 28 int f[maxn],a[maxn][3],b[maxn][2],c[maxn]; 29 int find(int a) 30 { 31 return (f[a]==a?f[a]:f[a]=find(f[a])); 32 } 33 int main() 34 { 35 freopen("prog10.in","r",stdin); 36 freopen("prog10.out","w",stdout); 37 int t=read(); 38 while(t--){ 39 S.clear(); 40 int n=read(),cnt=0,cnt1=0; 41 bool flag=1; 42 clr(a,0),clr(b,0),clr(c,0); 43 rep(i,0,n<<1) f[i]=i; 44 rep(i,0,n){ 45 a[i][0]=read(); 46 a[i][1]=read(); 47 a[i][2]=read(); 48 if(!a[i][2]){ 49 b[cnt][0]=a[i][0]; 50 b[cnt++][1]=a[i][1]; 51 } 52 if(S.find(a[i][0])==S.end()){ 53 S.insert(a[i][0]); 54 c[cnt1++]=a[i][0]; 55 } 56 if(S.find(a[i][1])==S.end()){ 57 S.insert(a[i][1]); 58 c[cnt1++]=a[i][1]; 59 } 60 } 61 sort(c,c+cnt1); 62 rep(i,0,n){ 63 if(a[i][2]==1){ 64 f[find(lower_bound(c,c+cnt1,a[i][0])-c)]=find(lower_bound(c,c+cnt1,a[i][1])-c); 65 } 66 } 67 rep(i,0,cnt){ 68 if(find(lower_bound(c,c+cnt1,b[i][0])-c)==find(lower_bound(c,c+cnt1,b[i][1])-c)){ 69 flag=0;break; 70 } 71 } 72 if(flag) printf("YES "); 73 else printf("NO "); 74 } 75 return 0; 76 }