学步园

题目链接：http://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&category=114&problem=1346&mosmsg=Submission+received+with+ID+11780602

  赤裸的最长公共子序列

 坑爹的题，回车也算字符，只要是字符就要算才行，绝不能用scanf读取字符串 

 我用了滚动数组

#include <stdio.h>
#include <string.h>
#define MAXN 1005
char str1[MAXN], str2[MAXN];
int f[2][MAXN];

int main()
{
    int n, i, j;
    int len1, len2;
    int k1, k2;
    while( gets(str1))
    {
        gets(str2);
        len1 = strlen(str1);
        len2 = strlen(str2);
        memset(f,0,sizeof(f));
        for(i=1; i<=len1; ++i)
        for(j=1; j<=len2; ++j)
        {
            k1 = i &1;
            k2 = (i+1) & 1;
            if(str1[i-1] == str2[j-1])
                f[k1][j] = f[k2][j-1] + 1;
            else
            {
                if(f[k1][j-1] > f[k2][j])
                    f[k1][j] = f[k1][j-1];
                else
                    f[k1][j] = f[k2][j];
            }
        }
        printf("%d\n",f[len1 &1][len2]);
    }
    return 0;
}