Commit 0088bc7

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Merge pull request #7 from Shaily20/master

Added KMP Algorithm

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	`1`	`+#include <iostream>`
	`2`	`+#include<bits/stdc++.h>`
	`3`	`+using namespace std;`
	`4`	`+`
	`5`	`+/*`
	`6`	`+ * get prefix list`
	`7`	`+ */`
	`8`	`+vector<int> computePrefix(string str) {`
	`9`	`+`
	`10`	`+ int m=int(str.length());`
	`11`	`+ vector<int> prefix(m);`
	`12`	`+ for(int i=1,k=0;i<m;++i)`
	`13`	`+ {`
	`14`	`+ if(k>0&&str[i]!=str[k])`
	`15`	`+ k=prefix[k-1];`
	`16`	`+ if(str[k]==str[i])`
	`17`	`+ prefix[i]=++k;`
	`18`	`+ else`
	`19`	`+ prefix[i]=k;`
	`20`	`+ }`
	`21`	`+`
	`22`	`+ return prefix;`
	`23`	`+}`
	`24`	`+`
	`25`	`+void KMP(string &str, string pat) {`
	`26`	`+ int m = int(str.length());`
	`27`	`+ int n = int(pat.length());`
	`28`	`+ vector<int> longestPrefix = computePrefix(pat);`
	`29`	`+`
	`30`	`+ for (int i = 0, k = 0; i < m; ++i) {`
	`31`	`+ if (k > 0 && pat[k] != str[i])`
	`32`	`+ k = longestPrefix[k - 1];`
	`33`	`+ if (str[i] == pat[k])`
	`34`	`+ ++k;`
	`35`	`+ if (k == n) {`
	`36`	`+ cout << i - n + 1 << "\n";`
	`37`	`+ //more than one pattern`
	`38`	`+ k = longestPrefix[k - 1];`
	`39`	`+ }`
	`40`	`+`
	`41`	`+ }`
	`42`	`+}`
	`43`	`+`
	`44`	`+int main() {`
	`45`	`+ string s,p;`
	`46`	`+ cin>>s>>p;`
	`47`	`+ KMP(s,p);`
	`48`	`+ return 0;`
	`49`	`+}`

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