28

Author: mkmark

leetcode/28/0.in

@@ -0,0 +1,2 @@
+"aabaaabaaac"
+"aabaaac"

leetcode/28/main.cpp

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+/*
+author: [email protected]
+*/
+
+#include <bits/stdc++.h>
+#include "../../lib/LeetCodeInputTemplate.hpp"
+#include "solution-1.cpp"
+using namespace std;
+
+typedef vector<int> vi;
+typedef vector<vector<int>> vvi;
+
+int main()
+{
+    LeetCodeInput li("0.in");
+
+    auto l0 = li.get<string>(0);
+    auto l1 = li.get<string>(1);
+
+    chrono::steady_clock::time_point begin = chrono::steady_clock::now();
+    Solution solution;
+    auto output = solution.strStr(l0, l1);
+    chrono::steady_clock::time_point end = chrono::steady_clock::now();
+    cout << "Time difference = " << chrono::duration_cast<chrono::microseconds> (end - begin).count() << "µs" << endl;
+
+    cout << output << endl;
+
+    // for (int i: output){
+    //     cout << i << ' ';
+    // }
+
+    // for (auto i: output){
+    //     for (int j: i){
+    //         cout << j << ' ';
+    //     }
+    //     cout << '\n';
+    // }
+
+    return 0;
+}

leetcode/28/solution-1.cpp

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+/*
+author: [email protected]
+time: O(m+n)
+space: O(n)
+
+Runtime: 0 ms, faster than 100.00% of C++ online submissions for Find the Index of the First Occurrence in a String.
+Memory Usage: 6.2 MB, less than 60.31% of C++ online submissions for Find the Index of the First Occurrence in a String.
+kmp
+*/
+
+#include <bits/stdc++.h>
+
+using namespace std;
+
+#define all(x) begin(x), end(x)
+typedef vector<int> vi;
+typedef vector<vector<int>> vvi;
+
+class Solution {
+public:
+    int strStr(string text, string pattern) {
+        int m = size(text);
+        int n = size(pattern);
+        /// fallback array
+        int fb[n];
+        fb[0] = 0;
+        for (int i=1, j=0; i<n;){
+            if (pattern[i] == pattern[j]){
+                ++j;
+                fb[i] = j;
+                ++i;
+            } else {
+                if (j>0){
+                    j = fb[j-1];
+                } else {
+                    fb[i] = 0;
+                    ++i;
+                }
+            }
+        }
+
+        for (int i=0, j=0; i<=m;){
+            if (text[i] == pattern[j]){
+                ++i;
+                ++j;
+                if (j==n){
+                    return i-j;
+                }
+            } else {
+                if (j>0){
+                    j = fb[j-1];
+                } else {
+                    ++i;
+                }
+            }
+        }
+
+        return -1;
+    }
+};
+
+const static auto initialize = [] {
+    std::ios::sync_with_stdio(false);
+    std::cin.tie(nullptr);
+    std::cout.tie(nullptr);
+    return nullptr;
+}();

leetcode/28/solution.cpp

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+/*
+author: [email protected]
+time: O()
+space: O()
+
+Runtime: 0 ms, faster than 100.00% of C++ online submissions for Find the Index of the First Occurrence in a String.
+Memory Usage: 6.2 MB, less than 60.31% of C++ online submissions for Find the Index of the First Occurrence in a String.
+*/
+
+#include <bits/stdc++.h>
+
+using namespace std;
+
+#define all(x) begin(x), end(x)
+typedef vector<int> vi;
+typedef vector<vector<int>> vvi;
+
+class Solution {
+public:
+    int strStr(string haystack, string needle) {
+        return haystack.find(needle);
+    }
+};
+
+const static auto initialize = [] {
+    std::ios::sync_with_stdio(false);
+    std::cin.tie(nullptr);
+    std::cout.tie(nullptr);
+    return nullptr;
+}();