标签：hdu4857
1 5 10 3 5 1 4 2 5 1 2 3 4 1 4 2 3 1 5 3 5 1 2
1 2 3 4 5
input: 1 3 1 3 1 answer: 3 1 2 而不是 2 3 1
WA代码：正序拓扑
#include <cstdio>
#include <cstring>
#include <queue>
#define maxn 100002
using namespace std;
int head[maxn], indegree[maxn], ans[maxn];
struct Node{
int to, next;
} map[maxn];
void topoSort(int n)
{
priority_queue<int, vector<int>, greater<int> > Q;
int i, u, id = 1;
for(i = 1; i <= n; ++i)
if(!indegree[i]) Q.push(i);
while(!Q.empty()){
ans[id++] = u = Q.top(); Q.pop();
for(i = head[u]; i != -1; i = map[i].next)
if(!--indegree[map[i].to]) Q.push(map[i].to);
}
for(i = 1; i <= n; ++i)
if(i != n) printf("%d ", ans[i]);
else printf("%d\n", ans[i]);
}
int main()
{
int t, n, m, a, b, i;
scanf("%d", &t);
while(t--){
memset(indegree, 0, sizeof(indegree));
memset(head, -1, sizeof(head));
scanf("%d%d", &n, &m);
for(i = 0; i < m; ++i){
scanf("%d%d", &a, &b);
map[i].to = b;
map[i].next = head[a];
head[a] = i;
++indegree[b];
}
topoSort(n);
}
return 0;
}
#include <cstdio>
#include <cstring>
#include <queue>
#define maxn 100002
using namespace std;
int head[maxn], indegree[maxn], ans[maxn];
struct Node{
int to, next;
} map[maxn];
void topoSort(int n)
{
priority_queue<int> Q;
int i, u, id = 1;
for(i = 1; i <= n; ++i)
if(!indegree[i]) Q.push(i);
while(!Q.empty()){
ans[id++] = u = Q.top(); Q.pop();
for(i = head[u]; i != -1; i = map[i].next)
if(!--indegree[map[i].to]) Q.push(map[i].to);
}
for(i = n; i >= 1; --i)
if(i != 1) printf("%d ", ans[i]);
else printf("%d\n", ans[i]);
}
int main()
{
int t, n, m, a, b, i;
scanf("%d", &t);
while(t--){
memset(indegree, 0, sizeof(indegree));
memset(head, -1, sizeof(head));
scanf("%d%d", &n, &m);
for(i = 0; i < m; ++i){
scanf("%d%d", &a, &b);
map[i].to = a;
map[i].next = head[b];
head[b] = i;
++indegree[a];
}
topoSort(n);
}
return 0;
}HDU4857 逃生 【拓扑排序】,布布扣,bubuko.com
标签：hdu4857
原文地址：http://blog.csdn.net/chang_mu/article/details/38326143
