poj 2250Compromise

#include<stdio.h>
#include<string.h>
#include<math.h>
#include<algorithm>
using namespace std;
char text1[110][32];
int num1;
char text2[110][32];
int num2;
char ans[110][32];
int len;
#define left 1
#define up 2
#define upleft 3
int d[110][110];
int b[110][110];
void dp(int l1,int l2)
{
    if(strcmp(text1[l1-1],text2[l2-1])==0)
    {
        if(d[l1-1][l2-1]==-1)
        {
            dp(l1-1,l2-1);
        }
        d[l1][l2]=d[l1-1][l2-1]+1;
        b[l1][l2]=upleft;
        return;
    }
    if(d[l1-1][l2]==-1)
    {
        dp(l1-1,l2);
    }
    if(d[l1][l2]<d[l1-1][l2])
    {
        d[l1][l2]=d[l1-1][l2];
        b[l1][l2]=up;
    }
    if(d[l1][l2-1]==-1)
    {
        dp(l1,l2-1);
    }
    if(d[l1][l2]<d[l1][l2-1])
    {
        d[l1][l2]=d[l1][l2-1];
        b[l1][l2]=left;
    }
}
void back()
{
    int l1=num1;
    int l2=num2;
    while(1)
    {
        if(l1==0||l2==0)
        {
            break;
        }
        if(b[l1][l2]==upleft)
        {
            strcpy(ans[len++],text1[l1-1]);
            l1--;
            l2--;
            continue;
        }
        if(b[l1][l2]==up)
        {
            l1--;
            continue;
        }
        if(b[l1][l2]=left)
        {
            l2--;
            continue;
        }
    }
}
int main()
{
    char temp[32];
    while(scanf("%s",temp)!=EOF)
    {
        strcpy(text1[0],temp);
        num1=1;
        getchar();
        while(1)
        {
            scanf("%s",text1[num1++]);
            getchar();
            if(strcmp(text1[num1-1],"#")==0)
            {
                num1--;
                break;
            }
        }
        num2=0;
        while(1)
        {
            scanf("%s",text2[num2++]);
            getchar();
            if(strcmp(text2[num2-1],"#")==0)
            {
                num2--;
                break;
            }
        }
        memset(d,-1,sizeof(d));
        int i;
        for(i=0;i<=num1;i++)
        {
            d[i][0]=0;
        }
        for(i=0;i<=num2;i++)
        {
            d[0][i]=0;
        }
        dp(num1,num2);
        len=0;
        back();
        for(i=len-1;i>0;i--)
        {
            printf("%s ",ans[i]);
        }
        printf("%s\n",ans[0]);
    }
    return 0;
}

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