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clang-format and clang-tidy fixes for 0c7515e9

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github-actions 2021-09-01 19:34:09 +00:00
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commit edff958ab2
1 changed files with 33 additions and 28 deletions
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61
strings/z_function.cpp
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@ -1,24 +1,25 @@
/**
* @file
* @brief The [Z function](https://cp-algorithms.com/string/z-function.html) for finding occurences of a pattern
* within a piece of text with time and space complexity O(n + m)
* @details
* @brief The [Z function](https://cp-algorithms.com/string/z-function.html) for
* finding occurences of a pattern within a piece of text with time and space
* complexity O(n + m)
* @details
* DESCRIPTION
* 1. The Z-function for a string is an array of length n where the
* i-th element is equal to the greatest number of characters starting
* 1. The Z-function for a string is an array of length n where the
* i-th element is equal to the greatest number of characters starting
* from the position i that coincide with the first characters of s.
* 2. Eg string : ababb then z[2]=2 as s[2]=s[0] and s[3]=s[1] and s[4]!=s[2]
* @author [Ritika Gupta](https://github.com/RitikaGupta8734)
*/
#include <iostream> /// for IO operations
#include <iostream> /// for IO operations
#ifdef _MSC_VER
#include <string> /// for string (use this for MS Visual C++)
#else
#include <cstring> /// for string
#include <cstring> /// for string
#endif
#include <vector> /// for std::vector
#include <cassert> /// for assert
#include <cassert> /// for assert
#include <vector> /// for std::vector
/**
* @brief Generate the Z-function for the inputted string.
@ -27,12 +28,15 @@
*/
std::vector<int> Z_function(const std::string &pattern) {
int pattern_length = pattern.size();
std::vector<int> z(pattern_length,0);
for (int i = 1,l = 0,r = 0; i < pattern_length; i++) {
if(i<=r)z[i]=std::min(r-i+1,z[i-l]);
while(i+z[i]<pattern_length && pattern[z[i]]==pattern[i+z[i]]) z[i]++;
if(i+z[i]-1>r)r=i+z[i]-1;
std::vector<int> z(pattern_length, 0);
for (int i = 1, l = 0, r = 0; i < pattern_length; i++) {
if (i <= r)
z[i] = std::min(r - i + 1, z[i - l]);
while (i + z[i] < pattern_length && pattern[z[i]] == pattern[i + z[i]])
z[i]++;
if (i + z[i] - 1 > r)
r = i + z[i] - 1;
}
return z;
}
@ -41,36 +45,38 @@ std::vector<int> Z_function(const std::string &pattern) {
* @brief Using Z_function to find a pattern in a text
* \param[in] pattern string pattern to search
* \param[in] text text in which to search
* \returns a vector of starting indexes where pattern is found in the text
* \returns a vector of starting indexes where pattern is found in the text
*/
std::vector<int> find_pat_in_text(const std::string &pattern, const std::string &text) {
std::vector<int> find_pat_in_text(const std::string &pattern,
const std::string &text) {
int text_length = text.size(), pattern_length = pattern.size();
std::vector<int> z = Z_function(pattern+'#'+text);
std::vector<int> z = Z_function(pattern + '#' + text);
std::vector<int> matching_indexes;
for (int i = 0; i < text_length; i++) {
if(z[i+pattern_length+1]==pattern_length) matching_indexes.push_back(i);
if (z[i + pattern_length + 1] == pattern_length)
matching_indexes.push_back(i);
}
return matching_indexes;
}
}
/**
* @brief Self-test implementations
* @returns void
*/
static void test(){
static void test() {
// usual case
std::string text1 = "alskfjaldsabc1abc1abcbksbcdnsdabcabc";
std::string pattern1 = "abc";
std::vector<int> matching_indexes1=find_pat_in_text(pattern1,text1);
assert((matching_indexes1 == std::vector<int>{10,14,18,30,33}));
std::vector<int> matching_indexes1 = find_pat_in_text(pattern1, text1);
assert((matching_indexes1 == std::vector<int>{10, 14, 18, 30, 33}));
// corner case
std::string text2 = "greengrass";
std::string pattern2 = "abc";
std::vector<int> matching_indexes2=find_pat_in_text(pattern2,text2);
std::vector<int> matching_indexes2 = find_pat_in_text(pattern2, text2);
assert((matching_indexes2 == std::vector<int>{}));
}
@ -79,7 +85,6 @@ static void test(){
* @returns 0 on exit
*/
int main() {
test(); // run self-test implementations
return 0;
}