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求最大公共子串

#include <stdio.h>
#include <string.h>

int main1()
{
	char *str1 = "aocdfe";
	char *str2 = "aadapmcdfa";
	
	int longest = 0;  // 最大長度
	int i,j;
	int start = 0;
	
	for (i = 0; i < strlen(str1); i++)
	{
		for (j = 0; j < strlen(str2); j++)
		{
			int len = 0;
			if (str1[i] == str2[j])
			{
				int a, b;
				for (a = i, b = j; a<strlen(str1) && b<strlen(str2); a++, b++)
				{
					if (str1[a] == str2[b])
						len++;
					else
						break;
				}
			}
			if (len > longest)
			{
				longest = len;
				start = i;
			}
		}
	}
	
	for (i = start; i < longest+start; i++)
		printf ("%c", str1[i]);
	
	printf ("\n");
	
	return 0;
}



int main()
{
	char *str1 = "aodacdfe";
	char *str2 = "aadapmcdfea";
	
	int table[100][100] = {0};
	
	int i;
	int j;
	for (i = 0; i < strlen(str2); i++)
	{
		if (str1[0] == str2[i])
			table[0][i] = 1;
		else
			table[0][i] = 0;
	}
	
	for (i = 1; i < strlen(str1); i++)
	{
		if (str2[0] == str1[i])
			table[i][0] = 1;
		else
			table[i][0] = 0;
		
		for (j = 1; j < strlen(str2); j++)
		{
			if (str1[i] == str2[j])
			{
				table[i][j] = table[i-1][j-1] + 1;
			}
			else
			{
				table[i][j] = 0;
			}
		}
	}
	
	int start = 0;
	int longest = table[0][0];
	for (i = 1; i < strlen(str1); i++)
	{
		for (j = 1; j < strlen(str2); j++)
		{
			if (longest < table[i][j])
			{
				longest = table[i][j];
				start = i - longest + 1;
			}
		}
	}
	
	printf ("最大長度是:%d\n", longest);
	for (i = start; i < longest+start; i++)
	{
		printf ("%c", str1[i]);
	}
	printf ("\n");
	
	return 0;
}