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#include <stdio.h>
#include <string.h>
#include <arpa/inet.h>
#include <stdlib.h>
struct net {
unsigned int ip;
unsigned char cidr;
};
#define min(a,b) ((a)<(b)?(a):(b))
#define max(a,b) ((a)>(b)?(a):(b))
int main(int argc,char *argv[]) {
short in;
int maxcidr;
int i=0,j=0,len=0;
struct net list[65536];//don't do more than a /16!
char ips[64];//why not?
char *cidrs;
while((in=fgetc(stdin)) != -1) {
if(in=='\n') {
ips[i]=0;
if((cidrs=strchr(ips,'/')) != 0) {
*cidrs=0;
cidrs++;
}
list[len].ip=htonl(inet_addr(ips));
list[len].cidr=cidrs?atoi(cidrs):32;
i=0;
cidrs=0;
len++;
continue;
}
ips[i]=in;
i++;
if(i>63) {
printf("your have a line that is TOOO long. stick to IPv4.\n");
return 0;
}
}
//!!!warning!!! inefficient algo ahead!
for(i=0;i<len;i++) {
for(j=0;j<len;j++) {
if(list[i].cidr == list[j].cidr) {
if((list[i].ip ^ list[j].ip) >> (32-list[i].cidr) == 1) {
list[i].cidr--;
list[j].cidr--;
list[i].ip &= (0xffffffff << (32-list[i].cidr));
list[j].ip &= (0xffffffff << (32-list[j].cidr));
i=-1;//start over!
j=-1;//start over!
continue;
}
}
if(list[i].ip == list[j].ip && list[i].cidr != list[j].cidr) {
list[i].cidr = min(list[i].cidr,list[j].cidr);
list[j].cidr = min(list[i].cidr,list[j].cidr);
i=-1;//start over!
j=-1;//start over!
continue;
}
maxcidr=min(list[i].cidr,list[j].cidr);
if(list[i].cidr != list[j].cidr) {
if(list[i].ip >> (32-maxcidr) == list[j].ip >> (32-maxcidr) ) {
list[i].cidr = min(list[i].cidr,list[j].cidr);
list[j].cidr = min(list[i].cidr,list[j].cidr);
list[i].ip &= (0xffffffff << (32-list[i].cidr));
list[j].ip &= (0xffffffff << (32-list[j].cidr));
i=-1;//start over!
j=-1;//start over!
continue;
}
}
}
}
for(i=0;i<len;i++) {
printf("%d.%d.%d.%d/%d\n",list[i].ip>>24&255,list[i].ip>>16&255,list[i].ip>>8&255,list[i].ip&255,list[i].cidr);
}
return 0;
}
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