锘??xml version="1.0" encoding="utf-8" standalone="yes"?>
//1364284 2009-05-13 20:11:33 Accepted 2437 187MS 4444K 1362 B C++ no way
#include <iostream>
#include <vector>
using namespace std;
const int N = 1004;
typedef struct 

{
int vex;
int cost;
}node;
vector<node> vv[N];
int ans, e;
char path[N];
int num[N][N];//num[i][j]琛ㄧず璧板埌i緇撶偣鑺辮垂mod K 鐨勬渶灝忓?/span>
int n, m, s, k;
int pcnt;
void init()

{
for(int i = 1; i <= n; i++)
vv[i].clear();
ans = e = -1;
memset(num, -1, sizeof(num));
}
void make_graph()

{
int a, b, cost;
node cc;
for(int i = 0; i < m; i++)
{
scanf("%d%d%d", &a, &b, &cost);
cc.vex = b; cc.cost = cost;
vv[a].push_back(cc);
// follows the tunnels you can not go back to the starting burrow.
//琛ㄧず鍗曞悜鍥?br>
// cc.vex = a;
//vv[b].push_back(cc);
}
}
void dfs(int v,int costs)

{
int i,j,p,t;
if(path[v] =='P' && costs % k == 0 && (ans ==-1 || ans > costs || (ans == costs && v < e)))
{
ans = costs;
e = v;
}
j = vv[v].size();
if(!j)
return ;
for(i=0;i<j;i++)
{
p = vv[v][i].vex;
t = vv[v][i].cost + costs;
if(num[p][t%k] == -1 || num[p][t%k] > t)
{
num[p][t%k] = t;
dfs(p,t);
}
}
}
int main()

{
int T,i, kk;
scanf("%d", &T);
for(i = 1; i <= T; i++)
{
scanf("%d%d%d%d", &n, &m, &s, &k);
getchar();
scanf("%s", path + 1);
init();
make_graph();
dfs(s,0 );
cout<<"Case "<<i<<": "<<ans<<" "<<e<<endl;
}
return 0;
}
]]>
//1276949 2009-04-16 16:47:42 Accepted 1016 484MS 268K 918 B C++ no way
#include<iostream>
using namespace std;
int n,t;
int prime[38] =
{0,0,2,3,0,5,0,7,0,0,0,11,0,13,0,0,0,17,0,19,0,0,0,23,0,0,0,0,0,29,0,31,0,0,0,0,0,37};
bool used[20];//鏍囪i鏄惁鐢ㄨ繃
int pre_num[20];
void dfs(int v,int num)

{
int i;
if(num == n)
{
if(prime[v+1] !=0 )
{
cout<<"1";
for(i=2;i<t;i++)
cout<<" "<<pre_num[i];
cout<<endl;
}
return ;
}
else
{
for(i=1;i<=n;i++)
{
if(used[i] == false && prime[i+v] != 0 )
{
used[i] = true;
pre_num[t++] = i;
dfs(i,num+1);
used[i] = false;
t--;
}
}
}
}
int main()

{
int i,cas=1;
while(cin>>n)
{
cout<<"Case "<<cas++<<":"<<endl;
for(i=1;i<=n;i++)
used[i] = false;
used[1] = true;
t = 1;
pre_num[t++]=1;
dfs(1,1);
cout<<endl;
}
return 0;
}
]]>
http://acm.nankai.edu.cn/p1131.html
DP浠g爜
#include<iostream>
#include<string>
using namespace std;
const int N = 2001;//鐢?001 Runtime Error錛屼笉瑕佸紑寰楀お灝?/span>
int dp[N][N];//dp[i][j]琛ㄧず涓瞫鐨勫墠i涓瓧絎﹀尮閰嶅埌涓瞭鐨勫墠j涓瓧絎︾殑鏈灝忔鏁?/span>
int lens,lent;
char s[N],t[N];
int main()

{
int i,j;
while(scanf("%s%s",s,t)!=EOF)
{
lens = strlen(s);
lent = strlen(t);
for(i=0;i<=lens;i++)
dp[i][0] = i;
for(j=0;j<=lent;j++)
dp[0][j] = j;//鍙樻崲鍒扮j涓瓧絎︽渶澶氱敤j姝?/span>
for(i=1;i<=lens;i++) 
{
for(j=1;j<=lent;j++)//鐩爣涓叉寚閽?/span>
{
if(s[i-1] == t[j-1])
dp[i][j] = dp[i-1][j-1];
else //鏇存敼
dp[i][j] = dp[i-1][j-1] + 1;
if(dp[i][j] > dp[i-1][j] + 1)//鍒犻櫎絎琲涓?/span>
dp[i][j] = dp[i-1][j] + 1;
if(dp[i][j] > dp[i][j-1] + 1)//鎻掑叆絎琲涓?/span>
dp[i][j] = dp[i][j-1] + 1;
}
}
printf("%d\n",dp[lens][lent]);
}
return 0;
}
DFS浠g爜錛堝湪鍗楀紑JudgeOnline瓚呮椂錛?br>
#include<iostream>
#include<string>
using namespace std;
const int M = 10000000;
const int N = 2001;//鐢?001 Runtime Error錛屼笉瑕佸紑寰楀お灝?/span>
int dp[N][N];
int lens,lent;
char s[N],t[N];
int dfs(int i,int j)

{
int p,q,r,mins=M;
if(i == lens && j == lent )
return 0;
else if(i == lens && j != lent )
return lent - j;
else if(i != lens && j == lent )
return lens - i;
if(dp[i][j] != M) //鍋氳繃鐨勬病鏈夊繀瑕佸啀鍋?/span>
return dp[i][j];
if(s[i] == t[j])
mins = dfs(i+1,j+1);//涓嶇敤鏀瑰彉
else
{
p = dfs(i+1,j+1) + 1;//淇敼
q = dfs(i+1,j) + 1;//鍒犻櫎
r = dfs(i,j+1) + 1;//鎻掑叆
if(p > q)
mins = q;
else
mins = p;
if(mins > r)
mins = r;
}
dp[i][j] = mins;
return mins;
}
int main()

{
int i,j;
while(scanf("%s%s",s,t)!=EOF)
{
lens = strlen(s);
lent = strlen(t);
for(i=0;i<lens;i++)
for(j=0;j<lent;j++)
dp[i][j] = M;
dfs(0,0);
printf("%d\n",dp[0][0]);
}
return 0;
}
]]>
#include<iostream>
#include<algorithm>
using namespace std;
__int64 a[505],b[505],c[505];
__int64 temp[250005];
bool bsearch(__int64 v,int low,int high) //浜屽垎鏌ユ壘

{
int mid;
while(low <= high)
{
mid = (high + low)/2;
if(temp[mid] == v)
return true;
if( temp[mid] < v)
low = mid+1;
else
high = mid-1;
}
return false;
}
int partition(__int64 r[],int i,int j)

{
__int64 pivot = r[i];
while(i<j)
{
while(i<j && r[j] >= pivot)
j--;
if(i<j)
r[i++] = r[j];
while(i<j && r[i] <= pivot)
i++;
if(i<j)
r[j--] = r[i];
}
r[i] = pivot;
return i;
}
void quickSort(__int64 r[],int low,int high) //蹇帓

{
int pivotpos;
if(low < high)
{
pivotpos = partition(r,low,high);
quickSort(r , low , pivotpos-1);
quickSort(r , pivotpos+1 , high);
}
}
int main()

{
__int64 lena,lenb,lenc,cas=1;
while(scanf("%I64d%I64d%I64d",&lena,&lenb,&lenc)!=EOF)
{
__int64 i,j,n;
for(i=0 ; i < lena ; i++)
scanf("%I64d",&a[i]);
for(i=0 ; i < lenb ; i++)
scanf("%I64d",&b[i]);
for(i=0 ; i < lenc ; i++)
scanf("%I64d",&c[i]);
__int64 k=0;
for(i=0 ; i< lena; i++)
for(j=0 ; j< lenb; j++)
temp[k++] = a[i] + b[j];
//sort(temp+0,temp+k); //,comp
quickSort(temp,0,k-1);
printf("Case %I64d:\n",cas++);
scanf("%I64d",&n);
while(n--)
{
int ok = 0;
__int64 sum;
scanf("%I64d",&sum);
for(i=0; ok==0 && i<lenc ; i++)
{
if( bsearch( sum - c[i] ,0,k-1) )//if(binary_search(temp+0,temp+k,sum-c[i]))
ok = 1;
}
if(ok == 1)
printf("YES\n");
else
printf("NO\n");
}
}
return 0;
}
]]>
#include<iostream>
using namespace std;
char gra[8][8];
bool mark[8][8];
int m,n,t,ok;
int si,sj,ei,ej;
int dir[4][2]=
{-1,0,1,0,0,-1,0,1};
int fun(int a,int b)

{
if(a>b)
return a-b;
else
return b-a;
}
void dfs(int i,int j,int step)

{
int k,p,q;
if(ok == 1)
return ;
if(step == t)
{
if(i == ei && j == ej)
ok = 1;
return ;
}
k = fun(i,ei) + fun(j,ej) ;
if(step + k > t) //鏈蹇殑鏃墮棿閮戒笉鑳借蛋鍒幫紝鑲畾瀹岃泲浜?/span>
return ;
if(k % 2 != (t-step) % 2)//if((t - step - k) & 1) //濂囧伓鍓灊
return ;
/**//**//**//*
1 1 1 1 1 1
1 0 1 1 1 1
1 1 1 1 1 1
1 1 1 1 1 1
1 1 1 1 0 1
涓や釜0涔嬮棿鐨勫潗鏍囦箣宸負(fù)6錛屾槸鍋舵暟錛屽彧鑳借蛋鍋舵暟姝ユ墠鑳藉埌杈?br>
*/
for(k=0;k<4;k++)
{
p = i + dir[k][0];
q = j + dir[k][1];
if(p>=0 && p<m && q>=0 && q<n && gra[p][q]!='X' && mark[p][q] == 0)
{
mark[p][q] = 1;
dfs(p,q,step+1);
mark[p][q] = 0;
}
}
}
int main()

{
while(cin>>m>>n>>t && m+n+t)
{
int i,j,walls=0;
for(i=0;i<m;i++)
for(j=0;j<n;j++)
{
cin>>gra[i][j];
if(gra[i][j] == 'S')
{
si = i;
sj = j;
}
else if(gra[i][j] == 'D')
{
ei = i;
ej = j;
}
else if(gra[i][j] == 'X')
walls++;
mark[i][j] = 0;
}
if(n*m-walls<=t)
{
cout<<"NO"<<endl;
continue;
}
ok = 0;
mark[si][sj] = 1;
dfs(si,sj,0);
if(ok == 1)
cout<<"YES"<<endl;
else
cout<<"NO"<<endl;
}
return 0;
}
]]>
]]>
#include<iostream>
using namespace std;
int n;//鍗佸瓧璺彛鏁?/span>
int map[1001][1001];
int dist[1001],dp[1001];
void dijkstra(int v)//榪澃鏂壒鎷夌畻娉?/span>

{
int i,j,mins,index;
int *s = new int[n+1];
for(i=1;i<=n;i++)
{
dist[i] = map[i][v];
s[i] = 0;
}
dist[v] = 0;
s[v] = 1;
for(i=1;i<n;i++)
{
mins = 2000000;
for(j=1;j<=n;j++)
{
if(s[j]==0 && dist[j]<mins)
{
mins = dist[j];
index = j;
}
}
if(mins == 2000000)
break;
s[index] = 1;
for(j=1;j<=n;j++)
{
if(s[j]==0 && dist[j]>dist[index]+map[j][index])
dist[j] = dist[index]+map[j][index];
}
}
}
int dfs(int v)//璁板繂娉曟繁鎼?/span>

{
if(dp[v] != -1)
return dp[v];
if(v == 2)
return 1;
int i,temp,sum=0;
for(i=1;i<=n;i++)
{
if(map[v][i]!=2000000 && dist[v] > dist[i])//鏈夎礬鐩擱氳屼笖瑕佸幓鐨刬鐐瑰埌緇堢偣绔欑殑璺濈瑕佹瘮v鍒扮粓鐐圭珯鐨勮窛紱誨皬
{
temp = dfs(i);
sum += temp;
}
}
dp[v] = sum;
return sum;
}
int main()

{
while(cin>>n && n)
{
int i,j,d,m;
cin>>m;
for(i=1;i<=n;i++)
{
dp[i] = -1;
for(j=1;j<=n;j++)
map[i][j] = 2000000;
}
while(m--)
{
scanf("%d%d%d",&i,&j,&d);
map[i][j] = map[j][i] = d;//鏃犲悜鍥?/span>
}
//姹傚嚭鍚勭偣鍒扮粓鐐圭珯鐨勬渶鐭窛紱?/span>
dijkstra(2);//2涓虹粓鐐圭珯
dfs(1);//浠?鍑哄彂
cout<<dp[1]<<endl;
}
return 0;
}
]]>