Note: I'm unware whether I can ask question here. LMK if this post isn't suitable for guidelines. I'll delete it. ;-)
Hello, I'm having confusion about understanding the intuition behind the problem 431B — Shower Line.
I've read the problem statement and editorial it suggested this solution
Can anyone who has solved this problem please give me hint on how to come up with these arr[i][j] numbers in the loop
do
{
//01234
tmp = g[p[0]][p[1]] + g[p[1]][p[0]];
tmp += g[p[2]][p[3]] + g[p[3]][p[2]];
//1234
tmp += g[p[1]][p[2]] + g[p[2]][p[1]];
tmp += g[p[3]][p[4]] + g[p[4]][p[3]];
//234
tmp += g[p[2]][p[3]] + g[p[3]][p[2]];
//34
tmp += g[p[3]][p[4]] + g[p[4]][p[3]];
if(tmp > ans)
{
ans = tmp;
for(int i = 0 ; i < n ; ++i)
pans[i] = p[i];
}
}
while(next_permutation(p, p+n));
Thanks in advance :-)
Hi, You look one by one all cases(12345, 13245, 14235, ... ) with
next_permutation(), pls say me what are you not understandIsa_m The input is coming in this format:
I am unable to understand how the 1D cases(12345, 13245, 14235, ... ) are getting interpreted here in 2d matrix. I also could not found any explanation online.
they should talk in such order that the answer is maximum: example 12345 if 1 talk with 2 answer += g12 + g21, after 3 talk with 4 answer += g34 + g43, after 1 gone to shower, now remained 2345 in queue,
now: 2 talks with 3 and 4 talks with 5, after 2 gone to shower , now remained 345
now: 3 talks with 4 , after 3 gone to shower and remained 45
4 talks 5 , after 4 gone shower and remained 5
if i talks j answer += g[i][j] + g[j][i]
that makes sense thanks Isa_m
You are welcome.
The 1D matrix has the current permutation of the numbers 1 to 5. Now inside g[i][j] 2D array, you are using the elements of the permutation as the index.
for example, p = [5,3,4,1,2]
then g[p[0]][p[3]] is actually g[5][1], as p[0] = 5 and p[3] = 1.