📄 usaco 2_2_1 preface numbering 题解_leokan的blog.mht
字号:
main ()
{
int n;
ifstream filein ("preface.in");
filein >> n;
filein.close ();
for (int loop =3D 1; loop <=3D n; ++loop) {
roman (loop);
}
ofstream fileout ("preface.out");
if (Ig !=3D 0) {
fileout << 'I' << ' ' << Ig << endl;
}
if (Vg !=3D 0) {
fileout << 'V' << ' ' << Vg << endl;
}
if (Xg !=3D 0) {
fileout << 'X' << ' ' << Xg << endl;
}
if (Lg !=3D 0) {
fileout << 'L' << ' ' << Lg << endl;
}
if (Cg !=3D 0) {
fileout << 'C' << ' ' << Cg << endl;
}
if (Dg !=3D 0) {
fileout << 'D' << ' ' << Dg << endl;
}
if (Mg !=3D 0) {
fileout << 'M' << ' ' << Mg << endl;
}
fileout.close ();
return (0);
}
</STRONG></PRE>
<H3>lifuxin's Algorithm</H3>
<P><STRONG>Similar as Alex's program, this one is simpler in some =
ways. We=20
can treat those things like "IX" or "IV" as another positive =
number. We=20
will just use the number to try every number in the ns array. I =
also used=20
match1 and match2 to save the corresponding letter of each number =
in ns.=20
</STRONG></P><PRE><STRONG>#include <stdio.h>
int ns[] =3D
{1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1};
//"M" "CM" "D" "CD" "C" "XC" "L" "XL" "X" "IX" "V" "IV" "I"
char rs[] =3D {"IVXLCDM"};
int match1[] =3D {6, 4, 5, 4, 4, 2, 3, 2, 2, 0, 1, 0, 0};
int match2[] =3D {-1, 6, -1, 5, -1, 4, -1, 3, -1, 2, -1, 1, -1};
int n;
int counts[7];
void=20
count (int num)
{
int sct[] =3D {3, 1, 1, 1, 3, 1, 1, 1, 3, 1, 1, 1, 3};
int i, j =3D 0;
for (i =3D 0; i < 13; i++) {
while (sct[i] > 0) {
if ((num - ns[i]) >=3D 0) {
num -=3D ns[i];
counts[match1[i]]++;
if (match2[i] >=3D 0)
counts[match2[i]]++;
sct[i]--;
}
else
break;
}
}
}
void=20
main ()
{
FILE *fp =3D fopen ("preface.in", "r");
FILE *wfp =3D fopen ("preface.out", "w");
int i;
fscanf (fp, "%d", &n);
for (i =3D 0; i < 7; i++)
counts[i] =3D 0;
for (i =3D 1; i <=3D n; i++)
count (i);
for (i =3D 0; i < 7; i++) {
if (counts[i])
fprintf (wfp, "%c %d\n", rs[i], counts[i]);
}
fclose (fp);
fclose (wfp);
}</STRONG></PRE></DIV></TD></TR></TBODY></TABLE><BR>
<DIV class=3Dopt><A =
title=3D=B2=E9=BF=B4=B8=C3=B7=D6=C0=E0=D6=D0=CB=F9=D3=D0=CE=C4=D5=C2=20
href=3D"http://hi.baidu.com/leokan/blog/category/Oi">=C0=E0=B1=F0=A3=BAOi=
</A> | <A=20
href=3D"http://hi.baidu.com/leokan/modify/blog/cfe41d38abe1a5f6b311c73b">=
=B1=E0=BC=AD</A> |=20
<A onclick=3D"return blogdel('blogdelform')"=20
href=3D"http://hi.baidu.com/leokan/blog/item/cfe41d38abe1a5f6b311c73b.htm=
l#">=C9=BE=B3=FD</A>=20
<FORM id=3Dblogdelform style=3D"DISPLAY: none" name=3Dblogdelform=20
action=3D/leokan/commit method=3Dpost><INPUT type=3Dhidden value=3D1 =
name=3Dct><INPUT=20
type=3Dhidden value=3D3 name=3Dcm><INPUT type=3Dhidden =
value=3Dcfe41d38abe1a5f6b311c73b=20
name=3DspBlogID><INPUT type=3Dhidden =
value=3Dhttp://hi.baidu.com/leokan/blog=20
name=3DspRefURL></FORM>
<SCRIPT language=3Djavascript>
<!--
function blogdel(str)
{
var pop=3Dnew Popup({ =
contentType:3,isReloadOnClose:false,width:340,height:80});
pop.setContent("title","=C9=BE=B3=FD=CE=C4=D5=C2");
=
pop.setContent("confirmCon","=C4=FA=C8=B7=B6=A8=D2=AA=B3=B9=B5=D7=C9=BE=B3=
=FD=D5=E2=C6=AA=CE=C4=D5=C2=BC=B0=C6=E4=CB=F9=D3=D0=C6=C0=C2=DB=C2=F0=A3=BF=
");
pop.setContent("callBack",delCallback);
pop.setContent("parameter",{fid:str,popup:pop});
pop.build();
pop.show();
return false;
}
function delCallback(para)
{
var o_pop=3Dpara["popup"];
o_pop.config.contentType=3D1;
o_pop.setContent("contentUrl","");
o_pop.reBuild();
G(para["fid"]).target=3Do_pop.iframeIdName;
eval("document."+para["fid"]).submit();
}
//-->
</SCRIPT>
| <A =
title=3D=BD=AB=B4=CB=CE=C4=D5=C2=CC=ED=BC=D3=B5=BD=B0=D9=B6=C8=CB=D1=B2=D8=
onclick=3D"return addToFavor();"=20
href=3D"http://cang.baidu.com/do/add" =
target=3D_blank>=CC=ED=BC=D3=B5=BD=CB=D1=B2=D8</A> | =E4=AF=C0=C0(<SPAN=20
id=3Dresult></SPAN>) | <A=20
href=3D"http://hi.baidu.com/leokan/blog/item/cfe41d38abe1a5f6b311c73b.htm=
l#send">=C6=C0=C2=DB</A> (0)
<SCRIPT language=3Djavascript>
/*<![CDATA[*/
var pre =3D [true,'USACO Translate USACO =D2=EB=CC=E2', 'USACO Translate =
USACO =D2=EB=CC=E2','/leokan/blog/item/a4d6d0c43fe3dfcf39db4991.html'];
var post =3D [true,'USACO 2.2.2 Subset Sums =CC=E2=BD=E2','USACO 2.2.2 =
Subset Sums =CC=E2=BD=E2', =
'/leokan/blog/item/83ab6e27a022a907908f9dcb.html'];
if(pre[0] || post[0]){
document.write('<div =
style=3D"height:5px;line-height:5px;"> </div><div id=3D"in_nav">');
if(pre[0]){
document.write('=C9=CF=D2=BB=C6=AA=A3=BA<a href=3D"' + pre[3] + '" =
title=3D"' + pre[1] + '">' + pre[2] + '</a> ');
}
if(post[0]){
document.write('=CF=C2=D2=BB=C6=AA=A3=BA<a href=3D"' + post[3] + '" =
title=3D"' + post[1] + '">' + post[2] + '</a>');
}
document.write('</div>');
}
/*]]>*/
</SCRIPT>
</DIV>
<DIV class=3Dline></DIV>
<STYLE type=3Dtext/css>#in_related_doc A {
TEXT-DECORATION: none
}
</STYLE>
<DIV id=3Din_related_tmp></DIV>
<SCRIPT language=3Djavascript type=3Dtext/javascript>
/*<![CDATA[*/
function HI_MOD_IN_RELATED_DOC_CALLBACK(arg){
if(arg.length <=3D 1) return false;
var hasMore =3D arg[0];
var D=3Dfunction(A,B){A[A.length]=3DB;}
if(arg.length % 2 =3D=3D 0) D(arg, ["","","",""]);
var html =3D ['<div id=3D"in_related_doc"><div =
class=3D"tit">=CF=E0=B9=D8=CE=C4=D5=C2=A3=BA</div>'];
D(html, '<table cellpadding=3D"0" cellspacing=3D"3" border=3D"0">');
for(var i =3D 1, j =3D arg.length; i < j; i +=3D 2){
D(html, '<tr>');
D(html, '<td width=3D"15px"><a style=3D"font-size:25px" =
>•</a></td><td><a href=3D"http://hi.baidu.com/' + arg[i][3] + =
'/blog/item/' + arg[i][2] + '.html" target=3D"_blank" title=3D"' + =
arg[i][0] + '">' + arg[i][1] + '</a>');
D(html, new Array(10).join('\u3000'));
D(html, '</td>');
if(arg[i + 1][0] !=3D "")
D(html, '<td width=3D"15px"><a style=3D"font-size:25px" =
>•</a></td><td><a href=3D"http://hi.baidu.com/' + arg[i + 1][3] + =
'/blog/item/' + arg[i + 1][2] + '.html" target=3D"_blank" title=3D"' + =
arg[i + 1][0] + '">' + arg[i + 1][1] + '</a></td>');
else
D(html, '<td> </td><td> </td>');
D(html, '</tr>');
}
if(hasMore) D(html, '<tr><td colspan=3D"4"><a target=3D"_blank" =
href=3D"/sys/search?pageno=3D1&type=3D7&sort=3D1&word=3DUSACO%202%2E2%2E1=
%20Preface%20Numbering%20%CC%E2%BD%E2&item=3Dcfe41d38abe1a5f6b311c73b">=B8=
=FC=B6=E0>></a></td></tr>');
D(html, '</table></div><div class=3D"line"> </div>');
var div =3D document.getElementById('in_related_tmp');
if(div){
div.innerHTML =3D html.join('');
while(div.firstChild){
div.parentNode.insertBefore(div.firstChild, div);
}
div.parentNode.removeChild(div);
}
}
if(RelatedDocData =3D=3D -1){ // not supported xhr
var script =3D document.createElement('script');
script.type =3D 'text/javascript';
script.src =3D =
'/sys/search?type=3D8&word=3DUSACO%202%2E2%2E1%20Preface%20Numbering%20%C=
C%E2%BD%E2&item=3Dcfe41d38abe1a5f6b311c73b&t=3D' + new Date().getTime();
document.getElementsByTagName('HEAD')[0].appendChild(script);
}else if(RelatedDocData =3D=3D null){
GetAndEval =3D true;
}else{
eval(RelatedDocData);
}
/*]]>*/
</SCRIPT>
<DIV id=3Din_reader>
<DIV class=3Dtit>=D7=EE=BD=FC=B6=C1=D5=DF=A3=BA</DIV>
<SCRIPT>
var g_spAnnony=3Dfalse;
var g_read=3D[
{}
];
g_read.length=3Dg_read.length-1;
var _rh1=3D"";
var _rh2=3D"";
function wrreader(){
_rh1 +=3D '<table width=3D"100%" ><tr>';
_rh2+=3D'<tr>';
if(g_spAnnony){
_rh1+=3D'<td align=3D"center" width=3D"10%" ><img border=3D"0" =
width=3D"55" height=3D"55" =
src=3D"http://img.baidu.com/hi/img/portraitn.jpg"></td>';
_rh2+=3D'<td> </td>';
if(g_read.length>0){
_rh1+=3D'<td align=3D"left" width=3D"12%">';
}else{
_rh1+=3D'<td align=3D"left" width=3D"100%">';
}
_rh1+=3D"<a =
href=3D'http://passport.baidu.com/?login&tpl=3Dsp&tpl_reg=3Dsp&u=3D"+myre=
f+"' =
target=3D'_self'>=B5=C7=C2=BC</a>=BA=F3=A3=AC=C4=FA=BE=CD=B3=F6=CF=D6=D4=DA=
=D5=E2=C0=EF=A1=A3</td>";
_rh2+=3D'<td> </td>'
}
if(g_read.length=3D=3D0){
if(!g_spAnnony){
_rh1+=3D'<td align=3Dleft =
width=3D"100%">=D7=EE=BD=FC=BB=B9=C3=BB=D3=D0=B5=C7=C2=BC=D3=C3=BB=A7=BF=B4=
=B9=FD=D5=E2=C6=AA=CE=C4=D5=C2=A1=AD=A1=AD</td>';
_rh2+=3D'<td> </td>';
}
}else{
for(i=3D0,len=3Dg_read.length;i<len;i++){
_rh1+=3D'<td align=3D"center" valign=3D"bottom" width=3D"10%" =
class=3D"user"><a href=3D"/'+g_read[i][0]+'" target=3D"_blank"><img =
border=3D"0" =
src=3D"http://himg.baidu.com/sys/portraitn/item/'+g_read[i][1]+'.jpg"></a=
></td>';
_rh2+=3D'<td align=3D"center" valign=3D"top" class=3D"user"><a =
href=3D"/'+g_read[i][0]+'" target=3D"_blank">'+g_read[i][2]+'</a></td>';
}
}
_rh1+=3D'<td width=3D"100%"></td></tr>';
_rh2+=3D'<td></td></tr></table>';
document.write(_rh1+_rh2);
}
wrreader();
</SCRIPT>
</DIV>
<DIV class=3Dline></DIV>
<SCRIPT language=3DJavaScript>
allkey=3Dallkey+"142d077b0bb076f40bd18714_cfe41d38abe1a5f6b311c73b_";
</SCRIPT>
<DIV id=3Din_comment><A name=3Dcomment></A>
<DIV class=3Dtit>=CD=F8=D3=D1=C6=C0=C2=DB=A3=BA</DIV>
<SCRIPT>
function writecmt(type,id,cmtname,cmturl,portraitId){
var html1=3D"";
if(type=3D=3D1){
html1=3D"<a name=3D'"+id+"' href=3D'"+cmturl+"' target=3D'_blank' =
title=3D'"+cmturl+"'><img border=3D'0' =
src=3D'http://himg.baidu.com/sys/portraitn/item/"+portraitId+".jpg'><br>"=
+cmtname+"</a>";
}else{
if(cmtname=3D=3D"" || cmtname=3D=3D"=C4=E4=C3=FB=CD=F8=D3=D1"){
if(cmturl=3D=3D""){
html1=3D"<a name=3D'"+id+"'>=C4=E4=C3=FB=CD=F8=D3=D1</a>";
}else{
html1=3D"<a name=3D'"+id+"' href=3D'"+cmturl+"' target=3D'_blank' =
title=3D'"+cmturl+"'>"+cmtname+"</a>";
}
}else{
if(cmturl=3D=3D""){
html1=3D"<div class=3D'f14' style=3D'display:inline'>=CD=F8=D3=D1:<a =
name=3D'"+id+"'>"+cmtname+"</a></div>";
}else{
html1=3D"<div class=3D'f14' style=3D'display:inline'>=CD=F8=D3=D1:<a =
name=3D'"+id+"' href=3D'"+cmturl+"' target=3D'_blank' =
title=3D'"+cmturl+"'>"+cmtname+"</a></div>";
}
}
}
document.write(html1);
}
</SCRIPT>
<DIV id=3Dpage></DIV></DIV>
<DIV id=3Din_send><A name=3Dsend></A>
<FORM id=3DpopFormSubmit name=3Dform1 onsubmit=3D"return checkcmtform()" =
action=3D/leokan/commit method=3Dpost><INPUT type=3Dhidden value=3D8 =
name=3Dct> <INPUT=20
type=3Dhidden value=3D1 name=3Dcm> <INPUT type=3Dhidden =
value=3Dcfe41d38abe1a5f6b311c73b=20
name=3DspBlogID>
<SCRIPT language=3DJavaScript>
document.write("<input type=3D'hidden' name=3D'spRefURL' =
value=3D'"+window.location.href+"'>");
</SCRIPT>
=20
<DIV class=3Dtit>=B7=A2=B1=ED=C6=C0=C2=DB=A3=BA</DIV>
<TABLE cellSpacing=3D5 cellPadding=3D0 width=3D620 border=3D0>
<TBODY>
<TR>
<TD class=3Df14>=D0=D5=A1=A1=C3=FB=A3=BA</TD>
<TD>gba1991 <INPUT id=3DspBlogCmtor style=3D"DISPLAY: none" =
maxLength=3D50=20
value=3Dgba1991 name=3DspBlogCmtor>
<DIV id=3Dnmerror style=3D"DISPLAY: =
none">*=D0=D5=C3=FB=D7=EE=B3=A4=CE=AA50=D7=D6=BD=DA</DIV></TD><INPUT=20
id=3DspBlogCmtURL style=3D"WIDTH: 360px" type=3Dhidden =
maxLength=3D128=20
onchange=3D'checkeandu("spBlogCmtURL")' =
value=3Dhttp://hi.baidu.com/leokan=20
name=3DspBlogCmtURL> </TR>
<TR id=3D2_err style=3D"DISPLAY: none">
<TD> </TD>
<TD>
<DIV class=3Derror id=3D2_err_con></DIV></TD></TR>
<TR>
<TD class=3Df14 vAlign=3Dtop>=C4=DA=A1=A1=C8=DD=A3=BA</TD>
<TD><TEXTAREA id=3DspBlogCmtText style=3D"WIDTH: 520px; HEIGHT: =
155px" onfocus=3DhidErr(3); tabIndex=3D3 =
name=3DspBlogCmtText></TEXTAREA>
<SCRIPT>
G("spBlogCmtor").value=3DG("spBlogCmtor").defaultValue;
G("spBlogCmtText").value=3D"";
</SCRIPT>
</TD></TR>
<TR id=3D3_err style=3D"DISPLAY: none">
<TD> </TD>
<TD>
<DIV class=3Derror id=3D3_err_con></DIV></TD></TR><INPUT =
type=3Dhidden=20
=
value=3DECA9B7FE2C4E560C0DB4A20D2CE9D25AEE9BBC3216379BE911B82C4EC4BE0636D=
E28A9226E734C2E7DA46C6EF0B049537D6AED9D559BCB19B7EA1CAF3518F8A5=20
name=3DspVcode> <INPUT id=3DspVerifyKey type=3Dhidden =
name=3DspVerifyKey>=20
<TR>
<TD class=3Df14 vAlign=3Dtop> </TD>
<TD class=3Df14 vAlign=3Dtop><INPUT id=3Dbtn_ok tabIndex=3D5 =
type=3Dsubmit value=3D=B7=A2=B1=ED=C6=C0=C2=DB =
name=3Dbtn_ok></TD></TR></TBODY></TABLE></FORM></DIV><BR></DIV>
<TABLE height=3D8 cellSpacing=3D0 cellPadding=3D0 width=3D"100%" =
border=3D0>
<TBODY>
<TR>
<TD class=3Dmodbl width=3D7> </TD>
<TD class=3Dmodbc> </TD>
<TD class=3Dmodbr =
width=3D7> </TD></TR></TBODY></TABLE></DIV></DIV></DIV></DIV>
<SCRIPT language=3Djavascript>
<!--
var hstr=3D"/leokan/brwstat?key1=3D1";
document.write("<script src=3D'"+hstr+"&key2=3D"+allkey+"'><\/script>");
//-->
</SCRIPT>
<BR>
<CENTER>
<DIV id=3Dft>©2008 Baidu</DIV></CENTER>
<SCRIPT>
if(document.getElementById("m_blog"))
{
var imgarray =3D =
document.getElementById("m_blog").getElementsByTagName('img');
var imgw =3D document.getElementById("m_blog").offsetWidth;
imgw =3Dimgw-40;
for(var i=3D0; i<imgarray.length; i++){
⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -