Codeforces 436 C. Dungeons and Candies

MST....

C. Dungeons and Candies time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output

During the loading of the game "Dungeons and Candies" you are required to get descriptions of k levels from the server. Each description is a map of an n?×?m checkered rectangular field. Some cells of the field contain candies (each cell has at most one candy). An empty cell is denoted as "." on the map, but if a cell has a candy, it is denoted as a letter of the English alphabet. A level may contain identical candies, in this case the letters in the corresponding cells of the map will be the same.

When you transmit infZ喎?http://www.Bkjia.com/kf/ware/vc/" target="_blank" class="keylink">vcm1hdGlvbiB2aWEgYSBuZXR3b3JrLCB5b3Ugd2FudCB0byBtaW5pbWl6ZSB0cmFmZmljIKGqIHRoZSB0b3RhbCBzaXplIG9mIHRoZSB0cmFuc2ZlcnJlZCBkYXRhLiBUaGUgbGV2ZWxzIGNhbiBiZSB0cmFuc21pdHRlZCBpbiBhbnkgb3JkZXIuIFRoZXJlIGFyZSB0d28gd2F5cyB0byB0cmFuc21pdCB0aGUgY3VycmVudCBsZXZlbCA8ZW0+QTwvZW0+OjwvcD4KPG9sPgo8bGk+CllvdSBjYW4gdHJhbnNtaXQgdGhlIHdob2xlIGxldmVsIDxlbT5BPC9lbT4uIFRoZW4geW91IG5lZWQgdG8gdHJhbnNtaXQgPGVtPm48L2VtPqGkPGVtPm08L2VtPiBieXRlcwogdmlhIHRoZSBuZXR3b3JrLjxsaT4KWW91IGNhbiB0cmFuc21pdCB0aGUgZGlmZmVyZW5jZSBiZXR3ZWVuIGxldmVsIDxlbT5BPC9lbT4gYW5kIHNvbWUgcHJldmlvdXNseSB0cmFuc21pdHRlZCBsZXZlbCA8ZW0+QjwvZW0+IChpZgogaXQgZXhpc3RzKTsgdGhpcyBvcGVyYXRpb24gcmVxdWlyZXMgdG8gdHJhbnNtaXQgPGVtPmQ8L2VtPjxlbT5BPC9lbT4sPzxlbT5CPC9lbT6hpDxlbT53PC9lbT4gYnl0ZXMsCiB3aGVyZSA8ZW0+ZDwvZW0+PGVtPkE8L2VtPiw/PGVtPkI8L2VtPiBpcwogdGhlIG51bWJlciBvZiBjZWxscyBvZiB0aGUgZmllbGQgdGhhdCBhcmUgZGlmZmVyZW50IGZvciA8ZW0+QTwvZW0+IGFuZCA8ZW0+QjwvZW0+LAogYW5kIDxlbT53PC9lbT4gaXMgYSBjb25zdGFudC4gTm90ZSwgdGhhdCB5b3Ugc2hvdWxkIGNvbXBhcmUgb25seSB0aGUgY29ycmVzcG9uZGluZyBjZWxscyBvZiBsZXZlbHMgPGVtPkE8L2VtPiBhbmQgPGVtPkI8L2VtPiB0bwogY2FsY3VsYXRlIDxlbT5kPC9lbT48ZW0+QTwvZW0+LD88ZW0+QjwvZW0+LgogWW91IGNhbm5vdCB0cmFuc2Zvcm0gdGhlIG1hcHMgb2YgbGV2ZWxzLCBpLmUuIHJvdGF0ZSBvciBzaGlmdCB0aGVtIHJlbGF0aXZlbHkgdG8gZWFjaCBvdGhlci4KPHA+CllvdXIgdGFzayBpcyB0byBmaW5kIGEgd2F5IHRvIHRyYW5zZmVyIGFsbCB0aGUgPGVtPms8L2VtPiBsZXZlbHMgYW5kIG1pbmltaXplIHRoZSB0cmFmZmljLjwvcD4KCgoKSW5wdXQKPHA+ClRoZSBmaXJzdCBsaW5lIGNvbnRhaW5zIGZvdXIgaW50ZWdlcnMgPGVtPm48L2VtPiw/PGVtPm08L2VtPiw/PGVtPms8L2VtPiw/PGVtPnc8L2VtPiAoMT+h3D88ZW0+bjwvZW0+LD88ZW0+bTwvZW0+P6HcPzEwOyAxP6HcPzxlbT5rPC9lbT4sPzxlbT53PC9lbT4/odw/MTAwMCkuCiBUaGVuIGZvbGxvd3MgdGhlIGRlc2NyaXB0aW9uIG9mIDxlbT5rPC9lbT4gbGV2ZWxzLiBFYWNoIGxldmVsIGlzIGRlc2NyaWJlZCBieSA8ZW0+bjwvZW0+IGxpbmVzLAogZWFjaCBsaW5lIGNvbnRhaW5zIDxlbT5tPC9lbT4gY2hhcmFjdGVycy4gRWFjaCBjaGFyYWN0ZXIgaXMgZWl0aGVyIGEgbGV0dGVyIG9mIHRoZSBFbmdsaXNoIGFscGhhYmV0IG9yIGEgZG90ICg="."). Please note that the case of the letters matters.

Output

In the first line print the required minimum number of transferred bytes.

Then print k pairs of integers x1,?y1,?x2,?y2,?...,?xk,?yk, describing the way to transfer levels. Pair xi, yi means that level xi needs to be transferred by way yi. If yi equals 0, that means that the level must be transferred using the first way, otherwise yi must be equal to the number of a previously transferred level. It means that you will transfer the difference between levels yi and xi to transfer level xi. Print the pairs in the order of transferring levels. The levels are numbered 1 through k in the order they follow in the input.

If there are multiple optimal solutions, you can print any of them.

Sample test(s) input

2 3 3 2
A.A
...
A.a
..C
X.Y
...

output

14
1 0
2 1
3 1

input

1 1 4 1
A
.
B
.

output

3
1 0
2 0
4 2
3 0

input

1 3 5 2
ABA
BBB
BBA
BAB
ABB

output

11
1 0
3 1
2 3
4 2
5 1

#include 
#include 
#include 
#include 
#include 

using namespace std;

struct Edge
{
    int u,v,w;
}edge[1100*1100];

bool cmp(Edge a,Edge b)
{
    return a.w vc[1100];

int get_diff(char a[][20],char b[][20] )
{
    int ret=0;
    for(int i=0;i