Submission #17658

#	Time	Username	Problem	Language	Result	Execution time	Memory
17658		Namnamseo	Senior Postmen (BOI14_postmen)	C++14	100 / 100	399 ms	20012 KiB

postmen

#include <cstdio>
#include <vector>
 
int n,m;
 
int start[ 500010];
int endp [1000010];
int next [1000010];
bool dead[1000010];
 
int counter;
 
void addEdge(int from,int to)
{
    next [counter] = start[from];
    start[from   ] = counter;
    endp [counter] = to;
    ++counter;
}
 
int stack[500010];
int hi   [500010];
int top=-1;
 
void push(int x) { stack[++top]=x; }
int  pop (     ) { return stack[top--]; }
 
bool visited[500010];
 
int main()
{
    counter=1;
    scanf("%d%d",&n,&m);
    int i,a,b;
    for(i=0;i<m;i++){
        scanf("%d%d",&a,&b);
        addEdge(a,b);
        addEdge(b,a);
    }
    push(1);
    int cur;
    int t=0;
    while(top>=0)
    {
        cur=stack[top];
        while(dead[start[cur]] && start[cur]) {
            start[cur]=next[start[cur]];
        }
        if(start[cur]==0) {
            hi[t++]=cur;
            --top;
            continue;
        } else {
            push(endp[start[cur]]);
            dead[start[cur]]=true;
            if(start[cur]%2){
                dead[start[cur]+1]=true;
            } else dead[start[cur]-1]=true;
        }
    }
    top=-1;
    int temp;
    for(i=0;i<t;++i)
    {
        cur = hi[i];
        //printf("%d ",cur);
        if(visited[cur])
        {
            while((temp=pop())!=cur) {
                printf("%d ",temp);
                visited[temp]=false;
            }
            printf("%d\n",cur);
            push(cur);
        } else {
            visited[cur]=true;
            push(cur);
        }
    }
}

Compilation message (stderr)

postmen.cpp: In function 'int main()':
postmen.cpp:33:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d",&n,&m);
     ~~~~~^~~~~~~~~~~~~~
postmen.cpp:36:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d",&a,&b);
         ~~~~~^~~~~~~~~~~~~~

• Subtask 1: 38 / 38
• Subtask 2: 17 / 17
• Subtask 3: 45 / 45