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WA11 code

used[u]=true;

for(int j=1;j<=n;j++)
    if(used[j])
        f[j][u]=max(f[j][pre[u]],map[pre[u]][u]);
--------------------------------------------------------------
AC code

for(int j=1;j<=n;j++)
    if(used[j])
        f[j][u]=max(f[j][pre[u]],map[pre[u]][u]);

used[u]=true;
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Take care of details.
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Helpful test data:
6 6
1 2 8
2 3 3
3 5 2
2 4 7
4 6 2
2 5 6
Ans:
Cost: 22
Cost: 25