int main(int argc,char *argv[]){
int num,i,iter,j,count=1,tmp;
double x,y;
double area;
scanf("%d",&num);
while(num){
iter=0;
area=0.0;
printf("Figure %d: ",count++);
if(num<3){
printf("Impossible\n");
for(j=0;j<num;j++)scanf("%lf %lf",&x,&y);
}
else{
for(i=0;i<num;i++){
scanf("%lf %lf",&(list[iter].x),&(list[iter].y));
if(area!=-1){
if(iter!=0){
area+=getarea(list[iter].x,list[iter].y,list[iter-1].x,list[iter-1].y);
}
if(iter>=3){
if(getarea(list[iter].x-list[iter-1].x,list[iter].y-list[iter-1].y,list[iter-1].x-list[iter-2].x,list[iter-1].y-list[iter-2].y)==0){
if(dot(list[iter].x-list[iter-1].x,list[iter].y-list[iter-1].y,list[iter-1].x-list[iter-2].x,list[iter-1].y-list[iter-2].y)<0)
area=-1;
}
for(j=0;j<iter-2;j++){
if(!check(list[j].x,list[j].y,list[j+1].x,list[j+1].y,list[iter-1].x,list[iter-1].y,list[iter].x,list[iter].y)){
area=-1;
}
}
}
}
iter++;
}
if(area==-1)printf("Impossible\n");
else{
iter--;
if(getarea(list[0].x-list[iter].x,list[0].y-list[iter].y,list[iter].x-list[iter-1].x,list[iter].y-list[iter-1].y)==0){
if(dot(list[0].x-list[iter].x,list[0].y-list[iter].y,list[iter].x-list[iter-1].x,list[iter].y-list[iter-1].y)<0)
area=-1;
}
for(j=2;j<iter;j++){
if(!check(list[0].x,list[0].y,list[iter].x,list[iter].y,list[j].x,list[j].y,list[j-1].x,list[j-1].y)){
area=-1;
break;
}
}
if(area!=-1){
area+=getarea(list[0].x,list[0].y,list[i-1].x,list[i-1].y);
printf("%.2f\n",area<0?-area:area);
}
else
printf("Impossible\n");
}
}
scanf("%d",&num);
}
return 0;
}
int main()
{
char str[5];
while(scanf("%s", str)==1)
{
steps = 0;
while(scanf("%s", str)==1 && str[0]!='K')
{
switch(str[0])
{
case 'N': step[steps] = 0; break;
case 'W': step[steps] = 1; break;
case 'S': step[steps] = 2; break;
case 'E': step[steps] = 3; break;
}
steps++;
}
if(!steps) printf("1\n");
else
{
process();
printf("%d\n", getarea());
}
}
return 0;
}
/* Read in the section header table, if it is present. If a section
* header string table is given in the ELF header, then also load the
* string table contents.
*/
static int readsecthdrs(void)
{
int n;
if (!secthdrs)
return TRUE;
n = elffhdr.e_shnum;
if (!(secthdr = malloc(n * sizeof *secthdr)))
nomem();
if (fseek(thefile, elffhdr.e_shoff, SEEK_SET) ||
elfrw_read_Shdrs(thefile, secthdr, n) != n) {
err("%s: warning: invalid section header table offset.", thefilename);
secthdrs = FALSE;
return TRUE;
}
if (elffhdr.e_shstrndx != SHN_UNDEF) {
shshstr = secthdr + elffhdr.e_shstrndx;
if (!(sectstr = getarea(shshstr->sh_offset, shshstr->sh_size))) {
err("%s: warning: invalid string table location.", thefilename);
free(sectstr);
sectstr = NULL;
}
}
return TRUE;
}
void GetContourAreas(const contour *ci){
int nlevels, n;
float *areas;
nlevels=ci->nlevels;
areas = ci->areas;
for(n=0;n<nlevels;n++){
float *xnode, *ynode;
int ipoly,npolys;
int *polysize;
areas[n]=0.0;
xnode=ci->xnode[n];
ynode=ci->ynode[n];
polysize=ci->polysize[n];
npolys=ci->npolys[n];
for(ipoly=0;ipoly<npolys;ipoly++){
int j;
for(j=1;j<polysize[ipoly]-1;j++){
float area;
area=getarea(xnode,ynode,j);
areas[n]+=area;
}
xnode+=polysize[ipoly];
ynode+=polysize[ipoly];
}
}
}
/* rebind() does most of the grunt work. After checking over the ELF
* headers, the function iterates through the sections, looking for
* symbol tables containing non-local symbol. When it finds one, it
* loads the non-local part of the table and the associated string
* table into memory, and calls changesymbols(). If changesymbols()
* actually changes anything, the altered symbol table is written back
* out to the object file.
*/
static int rebind(void)
{
Elf32_Shdr *shdrs;
Elf32_Sym *symtab;
char *strtab;
unsigned offset, count;
int i;
if (!readheader())
return FALSE;
if (!(shdrs = getarea(ehdr.e_shoff, ehdr.e_shnum * sizeof(Elf32_Shdr))))
return err("invalid section header table.");
for (i = 0 ; i < ehdr.e_shnum ; ++i) {
if (shdrs[i].sh_type != SHT_SYMTAB && shdrs[i].sh_type != SHT_DYNSYM)
continue;
if (shdrs[i].sh_entsize != sizeof *symtab) {
err("symbol table of unrecognized structure ignored.");
continue;
}
offset = shdrs[i].sh_offset + shdrs[i].sh_info * sizeof *symtab;
count = shdrs[i].sh_size / sizeof *symtab - shdrs[i].sh_info;
if (!count)
continue;
if (!(symtab = getarea(offset, count * sizeof *symtab)))
return err("invalid symbol table");
if (!(strtab = getarea(shdrs[shdrs[i].sh_link].sh_offset,
shdrs[shdrs[i].sh_link].sh_size)))
return err("invalid associated string table");
if (changesymbols(symtab, strtab, count)) {
if (fseek(thefile, offset, SEEK_SET)
|| fwrite(symtab, sizeof *symtab, count, thefile) != count)
return err("unable to write to the object file");
}
free(symtab);
free(strtab);
}
free(shdrs);
return TRUE;
}
/* Extract the list of source files, if present. The source files are
* determined by loading the symbol table section (and its associated
* string table) and looking up symbols of type STT_FILE.
*/
static int getsrcfiles(textline **plines)
{
Elf64_Sym *syms;
char *nmstr;
textline *lines;
char *str;
unsigned strtab, count, i;
int j, n;
if (!secthdrs)
return 0;
for (i = 0 ; i < elffhdr.e_shnum ; ++i)
if (secthdr[i].sh_type == SHT_SYMTAB)
break;
if (i == elffhdr.e_shnum)
return 0;
count = secthdr[i].sh_size / secthdr[i].sh_entsize;
strtab = secthdr[i].sh_link;
if (!(syms = malloc(count * sizeof *syms)))
nomem();
if (fseek(thefile, secthdr[i].sh_offset, SEEK_SET))
return err("%s: invalid symbol table offset.", thefilename);
count = elfrw_read_Syms(thefile, syms, count);
if (!count)
return 0;
nmstr = getarea(secthdr[strtab].sh_offset, secthdr[strtab].sh_size);
if (!nmstr) {
free(syms);
return 0;
}
lines = gettextlines(count);
n = 0;
for (i = 0 ; i < count ; ++i) {
if (ELF64_ST_TYPE(syms[i].st_info) != STT_FILE)
continue;
str = nmstr + syms[i].st_name;
for (j = 0 ; j < n ; ++j)
if (!strcmp(lines[j].str, str))
break;
if (j == n)
append(lines + n++, "%s", str);
}
free(syms);
free(nmstr);
if (n)
*plines = lines;
else
free(lines);
return n;
}
void getipaddr(char *start, char **countrybuf, char **areabuf)
{
char *pos, *p_country = NULL, *p_area = NULL, buf[2][128];
memset(buf, 0, sizeof(buf));
unsigned int offset;
int len[2];
offset = getlong3(start);
pos = p_share + offset + 4;
char *byte = pos; // 标志字节
pos++;
switch (*byte) {
case 1:{ // 标志字节为1，表示国家和区域信息都被同时重定向
int countryOffset = getlong3(pos); // 重定向地址
pos+=3;
pos=p_share+countryOffset;
byte = pos; // 标志字节
pos++;
switch (*byte) {
case 2: // 标志字节为2，表示国家信息又被重定向
{
p_country=p_share+getlong3(pos);
pos=p_share+countryOffset+4;
p_area = getarea(pos);
}
break;
default: // 否则，表示国家信息没有被重定向
{
p_country=byte;
p_area = getarea(p_country+strlen(p_country)+1);
}
break;
}
}
break;
case 2: // 标志字节为2，表示国家信息被重定向
{
p_country=p_share+getlong3(pos);// 重定向地址
pos = p_share + offset + 8;
p_area = getarea(pos);
}
break;
default:{ // 否则，表示国家信息没有被重定向
p_country=byte;
p_area=getarea(p_country+strlen(p_country)+1);
}
break;
}
if (codetype == GBK_t){
my_iconv("utf8", "gbk", buf[0], sizeof(buf[0]), p_country, strlen(p_country));
my_iconv("utf8", "gbk", buf[1], sizeof(buf[1]), p_area, strlen(p_area));
//printf("buf:%s %s, %d %d\n", buf[0], buf[1], strlen(buf[0]), strlen(buf[1]));
len[0] = strlen(buf[0]), len[1] = strlen(buf[1]);
if (len[0]){
*countrybuf = (char *)malloc(len[0] + 1);
if (!(*countrybuf)){
perror("malloc");
exit(1);
}
memcpy(*countrybuf, buf[0], len[0]+1);
}else {
*countrybuf = NULL;
}
if (len[1]){
*areabuf = (char *)malloc(len[1] + 1);
if (!(*areabuf)){
perror("malloc");
exit(1);
}
memcpy(*areabuf, buf[1], len[1]+1);
}else {
*areabuf = NULL;
}
}else if (codetype == UTF_t){
len[0] = strlen(p_country), len[1] = strlen(p_area);
if (len[0]){
*countrybuf = (char *)malloc(len[0] + 1);
if (!(*countrybuf)){
perror("malloc");
exit(1);
}
memcpy(*countrybuf, p_country, len[0]+1);
}else {
*countrybuf = NULL;
}
if (len[1]){
*areabuf = (char *)malloc(len[1] + 1);
if (!(*areabuf)){
perror("malloc");
exit(1);
}
memcpy(*areabuf, p_area, len[1]+1);
}else {
*areabuf = NULL;
}
}
//printf("areabuf:%s %s\n", *countrybuf, *areabuf);
}
/* Extract the list of dependencies, if present. The program header
* table entry of type PT_DYNAMIC contains the dynamic info, which
* includes the dependent files, and the string table that contains
* the file names. However, the string table is referenced by its
* location in memory, as opposed to its location in the file, so
* the program header table needs to be searched again to find the
* part that will be loaded at that location.
*/
static int getlibraries(textline **plines)
{
Elf64_Dyn *dyns;
char *nmstr;
textline *lines;
char *str;
unsigned long strtab = 0, strsz = 0;
unsigned count, i, j, n;
if (!proghdrs)
return 0;
for (i = 0 ; i < elffhdr.e_phnum ; ++i)
if (proghdr[i].p_type == PT_DYNAMIC)
break;
if (i == elffhdr.e_phnum)
return 0;
count = proghdr[i].p_filesz / sizeof *dyns;
if (!(dyns = malloc(count * sizeof *dyns)))
nomem();
if (fseek(thefile, proghdr[i].p_offset, SEEK_SET))
return err("%s: invalid dynamic table offset.", thefilename);
count = elfrw_read_Dyns(thefile, dyns, count);
if (!count)
return 0;
n = 0;
for (i = 0 ; i < count ; ++i) {
if (dyns[i].d_tag == DT_STRTAB)
strtab = dyns[i].d_un.d_ptr;
else if (dyns[i].d_tag == DT_STRSZ)
strsz = dyns[i].d_un.d_val;
else if (dyns[i].d_tag == DT_NEEDED)
++n;
}
if (!strtab || !strsz)
return 0;
for (i = 0 ; i < elffhdr.e_phnum ; ++i)
if (strtab >= proghdr[i].p_vaddr
&& strtab < proghdr[i].p_vaddr + proghdr[i].p_filesz)
break;
if (i == elffhdr.e_phnum)
return 0;
if (!(nmstr = getarea(proghdr[i].p_offset + (strtab - proghdr[i].p_vaddr),
strsz)))
return 0;
lines = gettextlines(n);
n = 0;
for (i = 0 ; i < count ; ++i) {
if (dyns[i].d_tag != DT_NEEDED)
continue;
str = nmstr + dyns[i].d_un.d_val;
for (j = 0 ; j < n ; ++j)
if (!strcmp(lines[j].str, str))
break;
if (j == n)
append(lines + n++, "%s", str);
}
free(dyns);
free(nmstr);
if (n)
*plines = lines;
else
free(lines);
return n;
}
//获得ip所属地理信息,isp
int getipinfo(char *ipstr,localtmp *p_loc)
{
if (p_share == NULL){
perror("openshare...");
return -1;
}
char *pos = p_share;
int record_len=10;
char *firstip=0;
//把ip转为整数
unsigned int ip=htonl(inet_addr(ipstr));
firstip=p_begin; // first record position
int l=0;
int u=total_record;
int i=0;
char* findip=firstip;
unsigned int beginip=0;
unsigned int endip=0;
//二分法查找
while(l <= u)
{
i=(l+u)/2;
pos=firstip+i*RECORD_LEN;
beginip = getlong4(pos);
pos+=4;
if(ip<beginip)
{
u=i-1;
}
else
{
endip=getlong4(p_share+getlong3(pos));
if(ip>endip)
{
l=i+1;
}
else
{
findip=firstip+i*RECORD_LEN;
break;
}
}
}
int offset = getlong3(findip+4);
pos=p_share+offset;
endip= getlong4(pos); // 用户IP所在范围的结束地址
pos+=4;
unsigned int j=ntohl(beginip);
inet_ntop(AF_INET,&j,p_loc->beginip, INET6_ADDRSTRLEN);// 获得开始地址的IP字符串类型
j=ntohl(endip);
inet_ntop(AF_INET,&j,p_loc->endip, INET6_ADDRSTRLEN);// 获得结束地址的IP字符串类型
char *byte = pos; // 标志字节
pos++;
switch (*byte) {
case 1:{ // 标志字节为1，表示国家和区域信息都被同时重定向
int countryOffset = getlong3(pos); // 重定向地址
pos+=3;
pos=p_share+countryOffset;
byte = pos; // 标志字节
pos++;
switch (*byte) {
case 2: // 标志字节为2，表示国家信息又被重定向
{
p_loc->p_country=p_share+getlong3(pos);
pos=p_share+countryOffset+4;
p_loc->p_area = getarea(pos);
}
break;
default: // 否则，表示国家信息没有被重定向
{
p_loc->p_country=byte;
p_loc->p_area = getarea(p_loc->p_country+strlen(p_loc->p_country)+1);
}
break;
}
}
break;
case 2: // 标志字节为2，表示国家信息被重定向
{
p_loc->p_country=p_share+getlong3(pos);// 重定向地址
pos = p_share + offset + 8;
p_loc->p_area = getarea(pos);
}
break;
default:{ // 否则，表示国家信息没有被重定向
p_loc->p_country=byte;
p_loc->p_area=getarea(p_loc->p_country+strlen(p_loc->p_country)+1);
}
break;
}
//printf("%s %s\n", p_loc->p_country, p_loc->p_area);
return 0;
}
