Z-Algo

1. https://www.spoj.com/problems/QUERYSTR/ Code
2. https://www.spoj.com/problems/EPALIN/ Code
3. https://www.spoj.com/problems/FINDSR/ Code
4. https://codeforces.com/problemset/problem/471/D Code
5. https://www.spoj.com/problems/NHAY/ Code
6. https://codeforces.com/problemset/problem/126/B Code

TRIE

1. https://www.spoj.com/problems/SUBXOR/ Code
2. https://www.spoj.com/problems/PHONELST/ Code
3. https://icpcarchive.ecs.baylor.edu/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&problem=2683
4. http://codeforces.com/problemset/problem/706/D Code
5. http://codeforces.com/problemset/problem/665/E Code
6. http://codeforces.com/problemset/problem/282/E Code
7. http://codeforces.com/problemset/problem/271/D Code

Manacher Algorithm

1. https://www.spoj.com/problems/MSUBSTR/ Code
2. https://www.spoj.com/problems/LPS/ Code

Suffix Array

1. https://www.spoj.com/problems/DISUBSTR/ Code
2. https://www.codechef.com/INSQ2016/problems/INSQ16F
3. http://codeforces.com/contest/452/problem/E Code
4. https://www.hackerrank.com/challenges/ashton-and-string/problem Code
5. https://www.hackerrank.com/challenges/string-similarity/problem Code

String Hashing

1. http://codeforces.com/problemset/problem/514/C Code
2. http://codeforces.com/contest/159/problem/D Code
3. http://codeforces.com/contest/727/problem/E Code

Aho-corasick

1. https://www.spoj.com/problems/SUB_PROB/
2. https://www.codechef.com/problems/LYRC
3. https://www.codechef.com/JULY12/problems/FAVNUM
4. https://www.codechef.com/LTIME06/problems/QMARKS
5. http://codeforces.com/contest/163/problem/E

Palindromic tree

1. https://www.hackerrank.com/contests/world-codesprint-6/challenges/functional-palindromes Code
2. https://www.hackerrank.com/contests/world-codesprint-5/challenges/challenging-palindromes/problem
3. https://www.hackerearth.com/problem/algorithm/mancunian-and-fantabulous-genes-1/description/ Code

Random String problems:

1. http://codeforces.com/gym/101532/problem/F Code
2. http://codeforces.com/gym/101532/problem/D Code

Will add more soon!