南阳36

/*
状态转移方程如下 ai,bj分别代表a字符串和b字符串的i,j处的字符
        
            -> 0                            (i = j =0)
v[i,j] =    -> v[i-1][j-1]                  (ai == bj)
            -> Max(v[i-1][j],v[i][j-1])     (ai != bj)
*/
#include<cstdio>
#include<cstring>
#define Max(a,b) ((a)>(b)?(a):(b))
using namespace std;

char a[1005],b[1005];
int v[1005][1005];
int n,i,j;

int main()
{
    int n;
    scanf("%d",&n);
    while(n--)
    {
        scanf("%s%s",a,b);
        for(i=0; a[i]!=''; ++i)
        {
            for(j=0; b[j]!=''; ++j)
            {
                if(a[i] == b[j])
                    v[i+1][j+1] = v[i][j] + 1;
                else
                    v[i+1][j+1] = Max(v[i][j+1],v[i+1][j]);
            }
        }
        printf("%d
",v[i][j]);
    }
    return 0;
}

//空间优化，只有一维时，v[i-1][j-1]会被覆盖，所以只需要开一个变量存储v[i-1][j-1]即可
#include<cstdio>
#include<cstring>
using namespace std;

char a[1005],b[1005];
int v[1005];
int n,i,j,t,temp;

int main()
{
    scanf("%d",&n);
    while(n--)
    {
        scanf("%s%s",a,b);
        memset(v,0,sizeof v);
        for(i=0; a[i]!=''; ++i)
        {
            t = 0;
            for(j=0; b[j]!=''; ++j)
            {
                temp = v[j];
                if(a[i] == b[j])
                    v[j] = t + 1;
                else if(v[j] < v[j-1])
                    v[j] = v[j-1];
                t = temp;
            }
        }
        printf("%d
",v[j-1]);
    }
    return 0;
}