# MAGICAL TRANSFORMATION

Its a question on minimum distance or the minimum steps required to convert a given String to another String.The Only addition step here is that we can swap 2 variables.
Here is the Link Of the question:http://www.codechef.com/INLO2015/problems/MOUSCH01
Now this can be solved by DP.In the case of swap I have used an additional step which is in my solution

``````#include<stdio.h>

#include<string.h>

#define LARGE 100000

int T[101][101];

char a[101];

char b[101];

int MIN(int a, int b) {

return a < b ? a : b;
``````

}

``````int min(int a,int b,int c){

return MIN(MIN(a, b), c);
``````

}

``````void dispaly(int m,int n){

int i,j;

for(i=0;i<=m;i++){

for(j=0;j<=n;j++)

printf("%d ",T[i][j]);

printf("\n");
}

}
int minChange(char *a,char *b,int m,int n){

int i=0,j=0,u,v,w,x,a1,b1=LARGE;

char t;

for(j=0;j<=n;j++){
T[0][j]=j;

}

for(i=0;i<=m;i++){

T[i][0]=i;
``````

}
//dispaly(m,n);

for(i=1;i<=m;i++){

``````for(j=1;j<=n;j++){

u=T[i-1][j]+1;

v=T[i][j-1]+1;

w=T[i-1][j-1]+(a[i-1]!=b[j-1]);

a1=min(u,v,w);

//The case Of swapping is checked

if(j>=2){
if(a[i-1]==b[j-2]&& a[i-2]==b[j-1])
b1=T[i-2][j-2]+1;
}
a1=MIN(a1,b1);

T[i][j]=a1;

}
b1=LARGE;
``````

}

return T[m][n];

}
int main(){

int t=0,l1,l2;

scanf("%d",&t);

``````while(t-- > 0){

scanf("%s%s",a,b);

l1=strlen(a);

l2=strlen(b);

printf("%d\n",minChange(a,b,l1,l2));

}
//getch();
``````

return 0;

}

The question is similar to the:http://www.geeksforgeeks.org/dynamic-programming-set-5-edit-distance/
only the the addition step in the question is of swapping

I am getting wrong ans plz help

The substructure is given in the article.

http://www.codechef.com/viewsolution/6810175 My solution for reference.

Can you suggest about the Transposition Step??How They are calculatiing

Terima kasih dan salam kenal.