Toplogical Sort

Revision en1, by Anushi1998, 2017-11-18 20:48:36

Usually, topological sort is implemented like

void dfs(int x) {
    vis[x] = true;
    for(int u = 0; u < n; u++) {
        if(!vis[u] && graph[x][u] == 1) {
            dfs(u);
        }
    }
    order.push_back(x);
}

And then printed in reverse order But if I implement this way

void dfs(int x) {
    order.push_back(x);
    vis[x] = true;
    for(int u = 0; u < n; u++) {
        if(!vis[u] && graph[x][u] == 1) {
            dfs(u);
        }
    }
}

And print in same order.

Can someone provide me a test case where 2nd approach will fail

Tags #graph, #algorithms

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en2 English Anushi1998 2017-11-18 21:43:46 12
en1 English Anushi1998 2017-11-18 20:48:36 619 Initial revision (published)