9252 LCS2
알고리즘(최장 공통 부분 수열)
1
1. LCS 알고리즘 사용하면 됨
구현법
1
1. 문자열 입력 받을 땐. cin.getline(char *c, size) 넣으면 된다.
코드
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
#include <iostream>
#include <cstring>
#define MAX_LENGTH 1000
using namespace std;
char a[MAX_LENGTH], b[MAX_LENGTH], lcs[MAX_LENGTH];
int map[MAX_LENGTH + 1][MAX_LENGTH + 1];
int al, bl, numOfLCS;
void getLCS();
int max(int a, int b) {
return a > b ? a : b;
}
int main() {
cin.getline(a, MAX_LENGTH+1);
cin.getline(b, MAX_LENGTH+1);
for (int i = 0; i < MAX_LENGTH; i++)
if (a[i] != 0)
al++;
else
break;
for (int i = 0; i < MAX_LENGTH; i++)
if (b[i] != 0)
bl++;
else
break;
getLCS();
cout << numOfLCS << endl;
for (int i = numOfLCS-1; i >= 0; i--)
cout << lcs[i];
cout << endl;
}
void getLCS() {
for (int i = 1; i <= bl; i++) {
for (int j = 1; j <= al; j++) {
if (b[i-1] == a[j-1])
map[i][j] = map[i-1][j-1]+ 1;
else
map[i][j] = max(map[i - 1][j], map[i][j - 1]);
}
}
int count = 0,start = al, before = map[bl][al]+1;
for (int i = bl; i >= 1; i--) {
for (int j = start; j >= 1; j--) {
if (before - 1 != map[i][j])
break;
if (map[i][j - 1] != map[i][j] && b[i - 1] == a[j - 1]) {
lcs[count++] = a[j - 1];
start = j - 1;ㅁ
before = map[i][j];
break;
}
}
if (start == 0)
break;
}
numOfLCS = count;
}