uva 531 Compromise

LCS，输出还是没有想出来。
#include<stdio.h>
#include<string.h>
#include<algorithm>
using namespace std;

int f[110][110],dp[110][110];
char s1[110][35],s2[110][35];
bool flag;

void fun(int i,int j)
{
    if(!i||!j) return;
    if(f[i][j]==1) {fun(i-1,j);return ;}
    if(f[i][j]==-1) {fun(i,j-1);return ;}
    fun(i-1,j-1);
    if(flag) printf(" %s",s1[i-1]);
    else{printf("%s",s1[i-1]);flag++;}
}
int main()
{
    int i,j,n1,n2;
    n1=n2=0;
    while(~scanf("%s",s1[n1]))
    {
        n1++;
        while(~scanf("%s",s1[n1])&&s1[n1][0]!='#') n1++;
        while(~scanf("%s",s2[n2])&&s2[n2][0]!='#') n2++;
        memset(dp,0,sizeof(dp));
        for(i=1;i<=n1;i++)
            for(j=1;j<=n2;j++)
        {
            if(!strcmp(s1[i-1],s2[j-1]))
            {
                dp[i][j]=dp[i-1][j-1]+1;
                f[i][j]=0;
            }
            else
                if(dp[i][j-1]>dp[i-1][j])
            {
                dp[i][j]=dp[i][j-1];
                f[i][j]=-1;
            }
            else
            {
                dp[i][j]=dp[i-1][j];
                f[i][j]=1;
            }
        }
        flag=0;
        fun(n1,n2);
        printf("
");
        n1=n2=0;
    }
    return 0;
}