Minimum Edits for Two Strings [closed] - c++

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I'm trying to use dynamic programming to determine the minimum edits required on one string
to transform it into another string
The code below does this, but I'm trying to find a way to keep track of the edits (d=delete, r=replace, i=insert).
For example:
string 1: sunflower
d rrrr <---Changes applying to string 1 (tracking minimum edits necessary to transform it into string 2)
string 2: sunlight
I'm not certain how to accomplish this, but I suspect it might have something to do with backtracking through the minimum distance table which is created. The code below finds the minimum distance perfectly fine, but I'm not certain how to approach keeping track of the necessary edits. Any ideas?
#include<iostream>
#include<cstring>
#define INSERT_COST 1
#define DELETE_COST 1
#define REPLACE_COST 1
using namespace std;
int min(int a,int b) {
return ((a < b) ? a : b);
}
/* convert str1 to str2 with minimum edits(insert,delete,replace)
suppose length(str1) = m and length(str2) = n
cost(i,j) -> cost of converting str1[0...i-1] to str2[0...j-1]
cost(m,n) -> cost of converting str1 to str2
Standard recursive formula for computing cost(m,n) :-
cost(i,j) = min[cost(i-1,j)+D, cost(i,j-1)+I, cost(i-1,j-1)+R]
D -> delete cost, I -> insert cost, R -> replace cost */
int editDistance(char str1[],int size1,char str2[],int size2) {
// cost matrix
// row -> str1 & col -> str2
int cost[size1][size2];
int i,j;
// initialize the cost matrix
for (i=0;i<size1;i++) {
for(j=0;j<size2;j++) {
if (i == 0) {
// source string is NULL
// so we need 'j' insert operations
cost[i][j] = j*INSERT_COST;
} else if (j == 0) {
// target string is NULL
// so we need 'i' delete operations
cost[i][j] = i*DELETE_COST;
} else {
cost[i][j] = -1;
}
}
} //initialization done
//compute cost(i,j) and eventually return cost(m,n)
for(i=1;i<size1;i++) {
for(j=1;j<size2;j++) {
int x = cost[i-1][j] + DELETE_COST;
int y = cost[i][j-1] + INSERT_COST;
// if str1(i-1) != str2(j-1), add the replace cost
// we are comparing str1[i-1] and str2[j-1] since
// the array index starts from 0
int z = cost[i-1][j-1] + (str1[i-1] != str2[j-1])*REPLACE_COST;
// as per our recursive formula
cost[i][j] = min(x, min(y,z));
}
}
// last cell of the matrix holds the answer
return cost[size1-1][size2-1];
}
//main
int main() {
char str1[] = "sunflower";
char str2[] = "sunlight";
int size1 = strlen(str1);
int size2 = strlen(str2);
int min_cost = editDistance(str1,size1+1,str2,size2+1);
cout<<"\nMinimum edits required to convert "<<str1<<
" to "<<str2<<" is "<<min_cost;
cout<<endl;
return 0;
}