C++ Programming Code Examples
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Implement Wagner and Fisher Algorithm for online String Matching
/* Implement Wagner and Fisher Algorithm for online String Matching
This is a C++ Program to implement online search. The Wagner-Fischer algorithm is a dynamic programming algorithm that measures the Levenshtein distance between two strings of characters.
For example, the Levenshtein distance between "kitten" and "sitting" is 3, since the following three edits change one into the other, and there is no way to do it with fewer than three edits. */
#include <stdio.h>
#include <math.h>
#include <string.h>
int d[100][100];
#define MIN(x,y) ((x) < (y) ? (x) : (y))
int main()
{
int i,j,m,n,temp,tracker;
char s[] = "Happy Codings - C Code Examples";
char t[] = "Programming Language Code Examples";
m = strlen(s);
n = strlen(t);
for(i=0;i<=m;i++)
d[0][i] = i;
for(j=0;j<=n;j++)
d[j][0] = j;
for (j=1;j<=m;j++)
{
for(i=1;i<=n;i++)
{
if(s[i-1] == t[j-1])
{
tracker = 0;
}
else
{
tracker = 1;
}
temp = MIN((d[i-1][j]+1),(d[i][j-1]+1));
d[i][j] = MIN(temp,(d[i-1][j-1]+tracker));
}
}
printf("the Levinstein distance is %d\n",d[n][m]);
return 0;
}
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