#include <stdio.h>
#include <string.h>
#define MAXLEN 200
void LCSLength(char *x, char *y, int m, int n, int c[MAXLEN][MAXLEN], int b[MAXLEN][MAXLEN])
{
int i, j;
for(i = 0; i <= m; i++)
c[i][0] = 0;
for(j = 0; j <= n; j++)
c[0][j] = 0;
for(i = 1; i<= m; i++)
{
for(j = 1; j <= n; j++)
{
if(x[i-1] == y[j-1])
{
c[i][j] = c[i-1][j-1] + 1;
b[i][j] = 0;
}
else if(c[i-1][j] >= c[i][j-1])
{
c[i][j] = c[i-1][j];
b[i][j] = 1;
}
else
{
c[i][j] = c[i][j-1];
b[i][j] = 2;
}
}
}
}
void PrintLCS(int b[MAXLEN][MAXLEN], char *x, int i, int j)
{
if(i == 0 || j == 0)
return;
if(b[i][j] == 0)
{
PrintLCS(b, x, i-1, j-1);
printf("%c", x[i-1]);
}
else if(b[i][j] == 1)
PrintLCS(b, x, i-1, j);
else
PrintLCS(b, x, i, j-1);
}
void main()
{
int m,n;
char x[MAXLEN],y[MAXLEN];
int b[MAXLEN][MAXLEN];
int c[MAXLEN][MAXLEN];
printf("请输入m并输入x字符串:\n");
scanf("%d\n",&m);
gets(x);
/*for(int i=0;i<m;i++)
{
x[i]=getchar();
}*/
printf("请输入n并输入y字符串:\n");
scanf("%d\n",&n);
for(int j=0;j<n;j++)
{
y[j]=getchar();
}
printf("m=%d,n=%d\n",m,n);
printf("最长公共子序列是:\n");
LCSLength(x, y, m, n, c, b);
int length=c[m][n];
PrintLCS(b, x, m, n);
printf("\n");
printf("最长公共子序列的长度是:\n");
printf("%d",length);
printf("\n");
}
