Poj3683 (2-set

poj3683

Title: There are several activities that can be selected in one of two time periods, asking for an allocation scheme that makes all activities non-conflicting.

Idea: 2set bare topic, sset need to do a strong unicom component decomposition, and then need to do a topological sequencing, but if the strong Unicom component decomposition using two times DFS, then you can save this step.

/** @author: Cwind*////#pragma COMMENT (linker, "/stack:102400000,102400000")#include <iostream>#include<map>#include<algorithm>#include<cstdio>#include<cstring>#include<cstdlib>#include<vector>#include<queue>#include<stack>#include<functional>#include<Set>#include<cmath>using namespacestd;#defineIOS Std::ios::sync_with_stdio (false); Std::cin.tie (0)#definePB Push_back#definePB Pop_back#defineBK Back ()#defineFS First#defineSe Second#defineSq (x) (x) * (x)#defineEPS (3E-7)#defineIinf (1<<29)#defineLinf (1ll<<59)#defineINF (1000000000)#defineFinf (1E3)#defineCLR (x) memset ((x), 0,sizeof (x));typedefLong Longll;typedef unsignedLong LongUll;typedef pair<int,int>Pii;typedef pair<int,int>P;Const intmaxn=2005;intN;inta[maxn][3];Charr[ -];vector<int>G[maxn],rg[maxn],od;BOOLVIS[MAXN];intSCCID[MAXN];int Get(CharACharb) {    return(A-'0')*Ten+b-'0';}BOOLInterintAintBintCintd) {    return! (a>=d| | b<=c);}voidAddedge (intAintb)    {G[A].PB (b); RG[B].PB (a);}voidDFS1 (intv) {Vis[v]=1;  for(intI=0; I<g[v].size (); i++){        intu=G[v][i]; if(!Vis[u]) dfs1 (U); } OD.PB (v);}voidDFS2 (intVintk) {Vis[v]=1; SCCID[V]=K;  for(intI=0; I<rg[v].size (); i++){        intu=Rg[v][i]; if(!Vis[u]) DFS2 (u,k); }}intV;voidSCC () {CLR (VIS); Od.clear ();  for(intI=1; i<=v;i++){        if(!Vis[i]) dfs1 (i);    } CLR (VIS); intId=1;  for(intI=od.size ()-1; i>=0; i--){        intv=Od[i]; if(!vis[v]) DFS2 (v,id++); }}voidbuild () { for(intI=1; i<=n;i++){         for(intj=i+1; j<=n;j++){            if(Inter (a[i][0],a[i][0]+a[i][2],a[j][0],a[j][0]+a[j][2]) {Addedge (i,j+N); Addedge (J,i+N); }            if(Inter (a[i][0],a[i][0]+a[i][2],a[j][1]-a[j][2],a[j][1]) {Addedge (i,j); Addedge (J+n,i+N); }            if(Inter (a[i][1]-a[i][2],a[i][1],a[j][0],a[j][0]+a[j][2]) {Addedge (i+n,j+N);            Addedge (J,i); }            if(Inter (a[i][1]-a[i][2],a[i][1],a[j][1]-a[j][2],a[j][1]) {Addedge (i+n,j); Addedge (J+n,i); }        }    }}BOOLANS[MAXN];intMain () {Freopen ("/home/slyfc/cppfiles/in","R", stdin); //freopen ("defense.in", "R", stdin); //freopen ("Defense.out", "w", stdout);Cin>>N; V=n*2;  for(intI=1; i<=n;i++) {scanf ("%s", R); a[i][0]=Get(r[0],r[1])* -+Get(r[3],r[4]); scanf ("%s", R); a[i][1]=Get(r[0],r[1])* -+Get(r[3],r[4]); scanf ("%d", &a[i][2]);    } build ();    SCC ();  for(intI=1; i<=n;i++){        if(sccid[i]==sccid[i+N]) {Puts ("NO"); return 0; }Else{            if(sccid[i]>sccid[i+N]) {Ans[i]=1; }Else{Ans[i]=0; }}} puts ("YES");  for(intI=1; i<=n;i++){        if(Ans[i]) {ints=a[i][0],t=a[i][0]+a[i][2]; printf ("%02d:%02d%02d:%02d\n", s/ -, s% -, t/ -, t% -); }Else{            ints=a[i][1]-a[i][2],t=a[i][1]; printf ("%02d:%02d%02d:%02d\n", s/ -, s% -, t/ -, t% -); }    }    return 0;}

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Poj3683 (2-set