Set consolidation: Difference between revisions

=={{header|C}}==

<lang c>#include <stdio.h>

#define s(x) (1U << ((x) - 'A'))

typedef unsigned int bitset;

int consolidate(bitset *x, int len)

{

int i, j;

for (i = len - 2; i >= 0; i--)

for (j = len - 1; j > i; j--)

if (x[i] & x[j])

x[i] |= x[j], x[j] = x[--len];

return len;

}

void show_sets(bitset *x, int len)

{

bitset b;

while(len--) {

for (b = 'A'; b <= 'Z'; b++)

if (x[len] & s(b)) printf("%c ", b);

putchar('\n');

}

}

int main(void)

{

bitset x[] = { s('A') | s('B'), s('C') | s('D'), s('B') | s('D'),

s('F') | s('G') | s('H'), s('H') | s('I') | s('K') };

int len = sizeof(x) / sizeof(x[0]);

puts("Before:"); show_sets(x, len);

puts("\nAfter:"); show_sets(x, consolidate(x, len));

return 0;

}</lang>