Submission #4665909

---

Source Code Expand

#include <cstdio>
#include <cstring>
#include <algorithm>
using namespace std;
const int N=1100000;
int num,h[N*2],a[N],b[N],root1,root2,p[N*2],n,f[N*2];
bool flag1;
struct node{
	int x,y,z,k,next;
	bool flag;
}data[N*10];
void link(int x,int y){
	++num;
	data[num].x=x;
	data[num].y=y;
	data[num].next=h[x];
	data[num].flag=true;
	data[num].k=num+1;
	h[x]=num;
	++num;
	data[num].x=y;
	data[num].y=x;
	data[num].next=h[y];
	data[num].flag=true;
	data[num].k=num-1;
	h[y]=num;
	p[x]++;p[y]++;
}
int dfs(int x){
	for(int i=h[x];i!=-1;i=data[i].next){
		if(!data[i].flag)continue;
		int v=data[i].y;
		h[x]=data[i].next;
		if(v==x+n)f[x]=1;
		if(v==x-n)f[x-n]=-1;
		data[i].flag=false;
		data[data[i].k].flag=false;
		return v;
	}
}
int main(){
//	freopen("1.in","r",stdin);
//	freopen("1.out","w",stdout);
	scanf("%d",&n);
	memset(h,-1,sizeof h);
	for(int i=1;i<=n;i++){
		scanf("%d",&a[i]);
		if(a[i]!=-1)link(i,a[i]);
		else link(i,0);
	}
	for(int i=1;i<=n;i++){
		scanf("%d",&b[i]);
		if(b[i]!=-1)link(i+n,b[i]+n);
		else link(i+n,0);
	}
	for(int i=1;i<=n;i++){
		if((p[i]%2)!=(p[i+n]%2)){
			printf("IMPOSSIBLE\n");
			return 0;
		}else if(p[i]%2==1)link(i,i+n);
	}
	printf("POSSIBLE\n");
	int opp=0;
	for(int i=1;i<=num/2;i++){
		opp=dfs(opp);
	}
	for(int i=1;i<=n;i++)printf("%d ",f[i]);
	
	return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:44:16: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
                ^
./Main.cpp:47:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d",&a[i]);
                    ^
./Main.cpp:52:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d",&b[i]);
                    ^

Judge Result