程序代码：
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <math.h>
int compares(void *a, void *b);
int makeresult( struct s *des, struct s *src);
void printresult(struct s *input);
struct s {
int value;
int row;
int col;
};
int main(void)
{
clock_t t = clock();
int i = 0, j = 0;
struct s result[4];
struct s tmp[16];
int matrix[4][4] = {
{1, 3, 5, 7, },
{1, 1, 3, 5, },
{3, 1, 1, 3, },
{5, 3, 1, 1, },
};
for( i = 0; i < 4; i += 1 )
for( j = 0; j < 4; j += 1 )
{
tmp[i * 4 + j].value = matrix[i][j];
tmp[i * 4 + j].row = i;
tmp[i * 4 + j].col = j;
}
for( i = 0; i < 16; i += 1 )
printf("%d%c", tmp[i].value, 0 == (i + 1 & 3) ? '\n' : ' ');
qsort(tmp, 16, sizeof tmp[0], compares);
if( 4 == makeresult(result, tmp) )
printresult(result);
else
printf("fatal error!\n");
printf("\nthis program cost %f second!\n", (double)(clock() - t) / CLOCKS_PER_SEC);
getchar();
return 0;
}
int compares(void *a, void *b)
{
if( ((struct s*)a)->value == ((struct s*)b)->value )
return ((struct s*)a)->row + ((struct s*)a)->col == ((struct s*)b)->row + ((struct s*)b)->col ?
((struct s*)a)->row > ((struct s*)b)->row ? 1 : -1
: ((struct s*)a)->row + ((struct s*)a)->col > ((struct s*)b)->row + ((struct s*)b)->col ? 1 : -1;
else
return ((struct s*)a)->value > ((struct s*)b)->value ? 1 : -1;
}
int makeresult( struct s *des, struct s *src)
{
int i = 0, j = 0, count = 0, row = 0, col = 0;
for( i = 0; i < 16; i += 1 )
if( -1 != src[i].value )
{
memcpy(des++, src + i, sizeof(struct s));
row = src[i].row;
col = src[i].col;
printf("%d, %d\n", src[i].row, src[i].col);
for( j = 0; j < 16; j += 1 )
{
if( src[j].row == row )
src[j].value = -1;
if( src[j].col == col )
src[j].value = -1;
}
count += 1;
}
else
continue;
return count;
}
void printresult(struct s *input)
{
int i = 0, sum = 0;
for( i = 0; i < 4; i += 1 )
{
printf("(%d, %d)\n", input[i].row, input[i].col);
sum += input[i].value;
}
printf("sum = %d\n", sum);
return;
}
不完全算法，当矩阵中的数字相差小的时候，结果不正确。
~~~
表示一面懵逼
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