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Diffstat (limited to 'path_max_probability.cpp')
-rw-r--r-- | path_max_probability.cpp | 52 |
1 files changed, 0 insertions, 52 deletions
diff --git a/path_max_probability.cpp b/path_max_probability.cpp deleted file mode 100644 index 467829e..0000000 --- a/path_max_probability.cpp +++ /dev/null @@ -1,52 +0,0 @@ -// 1514. Path with Maximum Probability -#include "leetcode.h" - -/* - * given an undirected weighted graph of 'n' nodes (0-indexed). represented by - * an edge list where 'edges[i] = [a, b]' is an undirected edge connecting the - * nodes 'a' and 'b' with a probability of success of traversing that edge - * 'succ_prob[i]'. given two nodes 'start, end', find the path with the maximum - * probability of success to go from 'start' to 'end' and return its success - * probability. if there is no path from 'start' to 'end', return 0. your answer - * will be accepted if it differs from the correct answer by at most '1e-5' - */ - -class Solution { -public: - double maxProbability(int n, vvd & edges, vector<double> &succ_prob, - int start, int end) { - vector<vector<pair<int, double>>> vvp(n); - for (int i = 0; i < edges.size(); i++) { - vvp[edges[i][0]].push_back({edges[i][1], succ_prob[i]}); - vvp[edges[i][1]].push_back({edges[i][0], succ_prob[i]}); - } - vector<int> seen(n, 0); - priority_queue<pair<double, int>> pqp; - pqp.push({(double)1.0, start}); - vector<double> mx(n, (double)0.0); - mx[start] = 1.0; - while (!pqp.empty()) { - auto top = pqp.top(); - pqp.pop(); - double prob_a = top.first; - int node = top.second; - if (!seen[node]) { - seen[node]++; - for (auto to : vvp[node]) - if (mx[to.first] < to.second * prob_a) { - mx[to.first] = to.second * prob_a; - pqp.push({mx[to.first], to.first}); - } - } - } - return mx[end]; - } -}; - -int main() { - Solution obj; - vvd e1 = {{0, 1}, {1, 2}, {0, 2}}, e2 = {{0, 1}, {1, 2}, {0, 2}}; - vector<double> sp1 = {0.5, 0.5, 0.2}, sp2 = {0.5, 0.5, 0.3}; - printf("%f\n", obj.maxProbability(3, e1, sp1, 0, 2)); // expect: 0.25000 - printf("%f\n", obj.maxProbability(3, e2, sp2, 0, 2)); // expect: 0.30000 -} |