백준 - 9252 LCS 2

[문제 링크]

LCS2는 다음 포스트에 있는 내용과 같다.

http://hsp1116.tistory.com/37

#include <cstdio>
#include <algorithm>
#include <vector>
#include <cstring>
using namespace std;
vector<char> output;
int cache[1001][1001];
char input[1001],compare[1000];
int LCS(int m,int n){
    memset(cache,0,sizeof(cache));
    for(int i=1;i<=m;i++){
        for(int j=1; j<=n;j++){
            if(compare[i-1] == input[j-1]){
                cache[i][j] = cache[i-1][j-1] +1;
                }
            else{
                cache[i][j] = std::max(cache[i-1][j], cache[i][j-1]);
            }
        }
    }
    return cache[m][n];
}
void backTracking(int m, int n){
    if(m==0 || n ==0) return;
    if(cache[m][n] > cache[m-1][n-1] && cache[m][n] > cache[m][n-1] && cache[m][n] > cache[m-1][n]){
        output.push_back(input[n-1]);
        backTracking(m-1, n-1);
    }else if(cache[m][n] > cache[m-1][n] && cache[m][n] == cache[m][n-1]){
        backTracking(m, n-1);
    }else{
          backTracking(m-1, n);
    }
}
int main(){
    scanf("%s%s",input,compare);
    int m = strlen(compare), n = strlen(input);
    printf("%d\n",LCS(m,n));
    backTracking(m,n);
    for(int i=output.size()-1;i>=0;i--)
        printf("%c",output[i]);
}