#include <stdio.h>
#include <memory.h>

#define MAX 1024

struct Triple
{
	int i,j; // row and column
	int value;
};

struct TMatrix
{
	struct Triple data[MAX]; // Triple
	int ndata; // number of data
	int rows; // row nums
	int cols; // col nums
};

void tmatrix_init(struct TMatrix* matrix)
{
	matrix->ndata = matrix->rows = matrix->cols = 0;
}

void tmatrix_print(struct TMatrix* matrix)
{
	int i,j;
	int k = 0;
	for(i=1;i<=matrix->rows;i++)
	{
		for(j=1;j<=matrix->cols;j++)
		{
			if(k<matrix->ndata && matrix->data[k].i==i && matrix->data[k].j==j)
			{
				printf("%3d ", matrix->data[k].value);
				k++;
			}else
			{
				printf("%3d ", 0);
			}
		}
		printf("\n");
	}
}

int main()
{
	// Init matrix m
	struct TMatrix m, t;
	tmatrix_init(&m);
	// Set m
	m.rows = 6;
	m.cols = 7;
	m.ndata = 8;
	m.data[0].i = 1;
	m.data[0].j = 2;
	m.data[0].value = 12;
	m.data[1].i = 1;
	m.data[1].j = 3;
	m.data[1].value = 9;
	m.data[2].i = 3;
	m.data[2].j = 1;
	m.data[2].value = -3;
	m.data[3].i = 3;
	m.data[3].j = 6;
	m.data[3].value = 14;
	m.data[4].i = 4;
	m.data[4].j = 3;
	m.data[4].value = 24;
	m.data[5].i = 5;
	m.data[5].j = 2;
	m.data[5].value = 18;
	m.data[6].i = 6;
	m.data[6].j = 1;
	m.data[6].value = 15;
	m.data[7].i = 6;
	m.data[7].j = 4;
	m.data[7].value = -7;
	// Fast Trans
	tmatrix_fast_transpose(&m, &t);
	// Print m
	//tmatrix_print(&m);
	tmatrix_print(&t);
	return 0;
}

// Transpose m to t
void tmatrix_fast_transpose(struct TMatrix* m, struct TMatrix* t)
{
	// Vars
	int nrows[MAX]; // Number of triple in new matrix t each row(t)
	int frows[MAX]; // First position in new matrix t each row(t)
	int i,j;
	// Basic dat
	t->rows = m->cols;
	t->cols = m->rows;
	t->ndata = m->ndata;
	// Calculate nrows(t), num of data same col in m
	memset(nrows, 0, MAX*sizeof(int));
	j=0;
	for(i=0;i<m->ndata;i++)
	{
		nrows[m->data[i].j]++;
	}
	// Calculate frows
	memset(frows, 0, MAX*sizeof(int));
	frows[1] = 0; // Matrix's row / col is 1/1, but in data, stores begin at [0]
	for(i=2;i<=m->ndata;i++)
	{
		frows[i] = frows[i-1] + nrows[i-1];
	}
	// Transpose
	for(i=0;i<m->ndata;i++)
	{
		t->data[frows[m->data[i].j]].j = m->data[i].i;
		t->data[frows[m->data[i].j]].i = m->data[i].j;
		t->data[frows[m->data[i].j]].value = m->data[i].value;
		frows[m->data[i].j]++;
	}

}

int kmp_index(char* s, char* p, int* next, int start)
{
	int i=start,j=0;
	int slen = strlen(s);
	int plen = strlen(p);
	while(i<slen && j<plen)
	{
		if(j==-1 || s[i]==p[j])
		{
			i++;
			j++;
		}else
		{
			j = next[j];
		}
	}
	if(j>=plen)
	{
		return i-plen;
	}else
	{
		return -1;
	}
}

int main()
{
	char* str = "xxabaabcacxxabaabcacdabaabcac99";
	char* pattern = "abaabcac";
	int next[MAX];
	int plen = strlen(pattern);
	int i;
	// Get next value
	get_next(pattern, next);
	for(i=0;i<plen;i++)
	{
		printf("%d ", next[i]);
	}
	printf("\n");
	// KMP Index
	i=0;
	while(i!=-1)
	{
		i = kmp_index(str, pattern, next, i);
		if(i!=-1)
		{
			printf("'%s' @ %dth of '%s'\n", pattern, i, str);
			i++;
		}
	}
	return 0;
}

#include <stdio.h>

int string_comp(char* s1, char* s2)
{
	char* p1 = s1;
	char* p2 = s2;	
	while(*p1!='\0' && *p2!='\0')
	{
		if(*p1>*p2)
		{
			return 1;
		}else if(*p1<*p2)
		{
			return -1;
		}else
		{
			p1++;
			p2++;
		}
	}
	// Length
	if(*p1=='\0' && *p2!='\0')
	{
		return -1;	
	}else if(*p1!='\0' && *p2=='\0')
	{
		return 1;
	}
	else
	{
		return 0;
	}
}

void string_copy(char* src, char* dst)
{
	while(*src!='\0')
	{
		*dst++ = *src++;
	}
	*dst = '\0';
}

// Append s2 to s1
void string_concat(char* s1, char* s2)
{
	// Go to end of s1
	while(*s1!='\0')
	{
		s1++;
	}
	// Copy s2
	while(*s2!='\0')
	{
		*s1++ = *s2++;
	}
	// End
	*s1 = '\0';
}

int string_length(char* s)
{
	int len = 0;
	while(*s!='\0')
	{
		s++;
		len++;
	}
	return len;
}

int main()
{
	char* s1 = "Liheyuanxx";
	char* s2 = "liheyuan";
	char buf[1024];
	printf("string_comp:%d\n", string_comp(s1, s2));
	string_copy(s1, buf);
	printf("copy result:%s\n", buf);
	string_concat(buf, s2);
	printf("concat result:%s\n", buf);
	printf("length:%d\n", string_length(buf));
	return 0;
}