P.S:正统方法：n*m*6（at most five oxygens），bfs O(6nm)
类似题目 https://www.cnblogs.com/cmyg/p/11108069.html
1 #include <bits/stdc++.h> 2 using namespace std; 3 const int maxn=110; 4 5 struct node 6 { 7 int x,y,z,t; 8 }; 9 10 struct cmp 11 { 12 bool operator() (node a,node b) 13 { 14 return a.t>b.t; 15 } 16 }; 17 18 priority_queue<node,vector<node>,cmp>st; 19 20 int dx[4]={-1,0,0,1}; 21 int dy[4]={0,-1,1,0}; 22 23 int f[maxn][maxn][6]; 24 char s[maxn][maxn]; 25 26 int main() 27 { 28 int n,m,x,y,z,t,xx,yy,zz,tt,i,j,k,r; 29 while (~scanf("%d%d",&n,&m)) 30 { 31 if (n==0) 32 break; 33 while (!st.empty()) 34 st.pop(); 35 36 for (i=1;i<=n;i++) 37 scanf("%s",s[i]+1); 38 for (i=1;i<=n;i++) 39 for (j=1;j<=m;j++) 40 if (s[i][j]=='S') 41 { 42 x=i; 43 y=j; 44 break; 45 } 46 for (i=1;i<=n;i++) 47 for (j=1;j<=m;j++) 48 for (k=0;k<=5;k++) 49 f[i][j][k]=1e9; 50 f[x][y][0]=0; 51 st.push({x,y,0,0}); 52 53 r=-1; 54 while (!st.empty()) 55 { 56 x=st.top().x; 57 y=st.top().y; 58 z=st.top().z; 59 t=st.top().t; 60 st.pop(); 61 62 if (r!=-1 && r<=t) 63 break; 64 65 for (i=0;i<4;i++) 66 { 67 xx=x+dx[i]; 68 yy=y+dy[i]; 69 zz=min(z+(s[xx][yy]=='B')-(s[xx][yy]=='#'),5); 70 tt=t+1-(s[xx][yy]=='P')+(s[xx][yy]=='#'); 71 if (zz>=0 && xx>=1 && xx<=n && yy>=1 && yy<=m && f[xx][yy][zz]>tt) 72 { 73 if (s[xx][yy]=='T') 74 { 75 if (r==-1) 76 r=tt; 77 else 78 r=min(r,tt); 79 } 80 81 f[xx][yy][zz]=tt; 82 st.push({xx,yy,zz,tt}); 83 } 84 } 85 } 86 87 printf("%d ",r); 88 } 89 return 0; 90 }
队友的方法是某每一个点按氧气量分成6个点，并连接旁边的点和设置对应的值，跑一遍spfa
1 #include <cstdio> 2 #include <cstdlib> 3 #include <cmath> 4 #include <cstring> 5 #include <time.h> 6 #include <string> 7 #include <set> 8 #include <map> 9 #include <list> 10 #include <stack> 11 #include <queue> 12 #include <vector> 13 #include <bitset> 14 #include <ext/rope> 15 #include <algorithm> 16 #include <iostream> 17 using namespace std; 18 #define ll long long 19 #define minv 1e-6 20 #define inf 1e9 21 #define pi 3.1415926536 22 #define nl 2.7182818284 23 const ll mod=1e9+7;//998244353 24 const int maxn=1e6+10; 25 26 struct node 27 { 28 char str[10]; 29 int _index; 30 }f[maxn]; 31 32 int k,g,_index; 33 char str[20],s[20]; 34 bool v[10]; 35 36 void dfs(int pos,int l) 37 { 38 int i; 39 for (i=pos;i<=k;i++) 40 if (i==k) 41 { 42 s[l]=0; 43 g++; 44 strcpy(f[g].str,s); 45 f[g]._index=_index; 46 } 47 else 48 { 49 s[l]=str[i]; 50 dfs(i+1,l+1); 51 } 52 } 53 54 int cmp(node a,node b) 55 { 56 return strcmp(a.str,b.str)<0; 57 } 58 59 int main() 60 { 61 int n,i,j,len,x,y; 62 while (~scanf("%d",&n)) 63 { 64 g=0; 65 for (_index=1;_index<=n;_index++) 66 { 67 scanf("%s",str); 68 len=strlen(str); 69 strcpy(s,str); 70 strcat(str,s); 71 for (i=0;i<len;i++) 72 { 73 s[0]=str[i]; 74 j=1; 75 k=i+len; 76 dfs(i+1,j); 77 } 78 } 79 sort(f+1,f+g+1,cmp); 80 81 x=0; 82 strcpy(f[g+1].str,""); 83 for (i=1;i<=g;i++) 84 { 85 v[f[i]._index]=1; 86 87 if (strcmp(f[i].str,f[i+1].str)!=0) 88 { 89 for (_index=1;_index<=n;_index++) 90 if (!v[_index]) 91 break; 92 if (_index==n+1) 93 { 94 len=strlen(f[i].str); 95 if (len>x) 96 { 97 x=len; 98 y=i; 99 } 100 } 101 102 for (_index=1;_index<=n;_index++) 103 v[_index]=0; 104 } 105 } 106 if (x==0) 107 printf("0 "); 108 else 109 printf("%s ",f[y].str); 110 } 111 return 0; 112 } 113 /* 114 2 115 ab 116 ba 117 */
1 #include <bits/stdc++.h> 2 using namespace std; 3 const int maxn=1e5+10; 4 5 int f[4][53],_index,card; 6 int value[15]={0,10,2,3,4,5,6,7,8,9,1,11,13,12}; 7 int cur,rep_card,rep_value; 8 int hap[14]; 9 int c,cc[53]; 10 int claim; 11 12 void replace_card() 13 { 14 int i; 15 c++; 16 cc[c]=f[_index][rep_card]; 17 18 for (i=rep_card;i<f[_index][0];i++) 19 f[_index][i]=f[_index][i+1]; 20 f[_index][0]--; 21 } 22 23 int find_num(int j) 24 { 25 int g=0,i; 26 for (i=1;i<=f[j][0];i++) 27 if (f[j][i]==card) 28 g++; 29 return g; 30 } 31 32 bool judge1() 33 { 34 int i; 35 for (i=1;i<=f[_index][0];i++) 36 if (f[_index][i]==card) 37 { 38 rep_card=i; 39 return 1; 40 } 41 return 0; 42 } 43 44 bool judge2() 45 { 46 int g=find_num(_index); 47 if (g==3 || g==4) 48 return 1; 49 else 50 return 0; 51 } 52 53 void get_rep_value() 54 { 55 int i; 56 rep_value=100; 57 for (i=1;i<=f[_index][0];i++) 58 if (value[f[_index][i]]<rep_value) 59 { 60 rep_value=value[f[_index][i]]; 61 rep_card=i; 62 } 63 } 64 65 void handle_value() 66 { 67 int i; 68 claim=0; 69 for (i=1;i<=f[_index][0];) 70 if (value[f[_index][i]]==rep_value) 71 { 72 claim++; 73 rep_card=i; 74 replace_card(); 75 } 76 else 77 i++; 78 } 79 80 void handle_card() 81 { 82 int i; 83 claim=0; 84 for (i=1;i<=f[_index][0];) 85 if (f[_index][i]==card) 86 { 87 claim++; 88 rep_card=i; 89 replace_card(); 90 } 91 else 92 i++; 93 } 94 95 ///one:value 96 void work1() 97 { 98 get_rep_value(); 99 if (rep_value!=100) 100 replace_card(); 101 } 102 103 ///many:value 104 void work2() 105 { 106 get_rep_value(); 107 handle_value(); 108 } 109 110 ///one:card 111 void work3() 112 { 113 replace_card(); 114 } 115 116 ///many:card 117 void work4() 118 { 119 handle_card(); 120 } 121 122 ///work2 123 void work5() 124 { 125 int g=100,i; 126 memset(hap,0,sizeof(hap)); 127 for (i=1;i<=f[_index][0];i++) 128 hap[f[_index][i]]++; 129 rep_value=100; 130 for (i=1;i<=13;i++) 131 if (hap[i]!=0 && (hap[i]<g || (hap[i]==g && value[i]<rep_value))) 132 { 133 g=hap[i]; 134 rep_value=value[i]; 135 } 136 handle_value(); 137 } 138 139 void show() 140 { 141 bool vis; 142 if (_index==0) 143 { 144 vis=judge1(); 145 if (vis) 146 { 147 work3(); 148 cur=1; 149 } 150 else 151 { 152 work1(); 153 cur=0; 154 } 155 claim=1; 156 } 157 else if (_index==1) 158 { 159 vis=judge1(); 160 if (vis) 161 { 162 work4(); 163 cur=1; 164 } 165 else 166 { 167 work1(); 168 cur=0; 169 claim=1; 170 } 171 } 172 else if (_index==2) 173 { 174 vis=judge1(); 175 if (vis) 176 { 177 work4(); 178 cur=1; 179 } 180 else 181 { 182 work5(); 183 cur=0; 184 } 185 } 186 else 187 { 188 vis=judge2(); 189 if (vis) 190 { 191 work4(); 192 cur=1; 193 } 194 else 195 { 196 work4(); 197 work1(); 198 if (rep_value!=100) 199 { 200 claim++; 201 cur=0; 202 } 203 else 204 cur=1; 205 } 206 } 207 } 208 209 bool next_lie(int j) 210 { 211 int next__index,next_card,i; 212 next__index=(_index+1)%4; 213 if (next__index!=j) 214 return 0; 215 next_card=card+1; 216 if (next_card==14) 217 next_card=1; 218 for (i=1;i<=f[next__index][0];i++) 219 if (f[next__index][i]==next_card) 220 return 0; 221 return 1; 222 } 223 224 bool zhiyi(int j) 225 { 226 if (j==0) 227 { 228 if (next_lie(j) || claim+find_num(j)>4) 229 return 1; 230 else 231 return 0; 232 } 233 else if (j==1) 234 { 235 if (next_lie(j)) 236 return 1; 237 else 238 return 0; 239 } 240 else if (j==2) 241 { 242 if (find_num(j)==4) 243 return 1; 244 else 245 return 0; 246 } 247 else 248 { 249 if (f[_index][0]==0) 250 return 1; 251 else 252 return 0; 253 } 254 } 255 256 void add_card(int j) 257 { 258 int i; 259 for (i=1;i<=c;i++) 260 f[j][++f[j][0]]=cc[i]; 261 } 262 263 void pr(int v) 264 { 265 if (v==1) 266 printf("A"); 267 else if (v==10) 268 printf("10"); 269 else if (v==11) 270 printf("J"); 271 else if (v==12) 272 printf("Q"); 273 else if (v==13) 274 printf("K"); 275 else 276 printf("%d",v); 277 } 278 279 int main() 280 { 281 int i,j; 282 char ch[5]; 283 while (~scanf("%s",ch)) 284 { 285 for (i=0;i<4;i++) 286 { 287 for (j=1;j<=13;j++) 288 { 289 if (!(i==0 && j==1)) 290 scanf("%s",ch); 291 if (ch[0]=='1') 292 f[i][j]=10; 293 else if (ch[0]=='J') 294 f[i][j]=11; 295 else if (ch[0]=='Q') 296 f[i][j]=12; 297 else if (ch[0]=='K') 298 f[i][j]=13; 299 else if (ch[0]=='A') 300 f[i][j]=1; 301 else 302 f[i][j]=ch[0]-48; 303 } 304 f[i][0]=13; 305 } 306 _index=0; 307 card=1; 308 c=0; 309 310 while (1) 311 { 312 // for (i=0;i<4;i++) 313 // { 314 // for (j=1;j<=f[i][0];j++) 315 // { 316 // pr(f[i][j]); 317 // if (j==f[i][0]) 318 // printf(" "); 319 // else 320 // printf(" "); 321 // } 322 // } 323 // printf("remain: "); 324 // for (i=1;i<=c;i++) 325 // { 326 // pr(cc[i]); 327 // if (i==c) 328 // printf(" "); 329 // else 330 // printf(" "); 331 // } 332 // printf(" "); 333 // printf("index=%d card=%d ",_index,card); 334 335 show(); 336 337 for (i=(_index+1)%4;i!=_index;i=(i+1)%4) 338 if (zhiyi(i)) 339 { 340 if (cur) 341 add_card(i); 342 else 343 add_card(_index); 344 c=0; 345 break; 346 } 347 348 if (f[_index][0]==0) 349 break; 350 351 _index=(_index+1)%4; 352 if (card==13) 353 card=1; 354 else 355 card++; 356 } 357 358 for (i=0;i<4;i++) 359 if (f[i][0]==0) 360 printf("WINNER "); 361 else 362 { 363 sort(f[i]+1,f[i]+f[i][0]+1); 364 for (j=1;j<=f[i][0];j++) 365 { 366 pr(f[i][j]); 367 if (j==f[i][0]) 368 printf(" "); 369 else 370 printf(" "); 371 } 372 } 373 } 374 return 0; 375 } 376 /* 377 A A 2 2 3 3 4 4 5 5 6 6 7 378 7 8 8 9 9 10 10 J J Q Q K K 379 A A 2 2 3 3 4 4 5 5 6 6 7 380 7 8 8 9 9 10 10 J J Q Q K K 381 382 A A A A 2 2 2 2 3 3 3 3 K 383 4 4 4 4 5 5 5 5 6 6 6 6 K 384 7 7 7 7 8 8 8 8 9 9 9 9 K 385 10 10 10 10 J J J J Q Q Q Q K 386 387 4 4 4 4 5 5 5 5 6 6 6 6 K 388 7 7 7 7 8 8 8 8 9 9 9 9 K 389 10 10 10 10 J J J J Q Q Q Q K 390 A A A A 2 2 2 2 3 3 3 3 K 391 392 A A 2 2 8 8 9 9 5 5 6 6 7 393 3 3 4 4 7 10 10 J J Q Q K K 394 A A 2 2 3 3 4 4 5 Q Q K K 395 5 6 6 7 7 8 8 9 9 10 10 J J 396 397 */
比赛后的改进方法：统计每位选手中每张牌的数目
1 #include <bits/stdc++.h> 2 using namespace std; 3 #define ll long long 4 #define minv 1e-6 5 #define inf 1e9 6 #define pi 3.1415926536 7 #define nl 2.7182818284 8 const ll mod=1e9+7;//998244353 9 const int maxn=1e5+10; 10 11 int value[14]={0,10,2,3,4,5,6,7,8,9,1,11,13,12}; 12 int card[4][14],x,y,v,table[14],nexty; 13 bool vis; 14 15 void work1() 16 { 17 vis=1; 18 v=1; 19 table[y]++; 20 card[x][y]--; 21 } 22 23 void work2() 24 { 25 int i; 26 vis=0; 27 for (i=1;i<=13;i++) 28 if (card[x][value[i]]) 29 break; 30 v=1; 31 table[value[i]]++; 32 card[x][value[i]]--; 33 } 34 35 void work3() 36 { 37 vis=1; 38 v=card[x][y]; 39 table[y]+=card[x][y]; 40 card[x][y]=0; 41 } 42 43 void work4() 44 { 45 int p=14,q,i; 46 vis=0; 47 for (i=1;i<=13;i++) 48 if (card[x][value[i]]!=0 && card[x][value[i]]<p) 49 p=card[x][value[i]],q=value[i]; 50 v=card[x][q]; 51 table[q]+=card[x][q]; 52 card[x][q]=0; 53 } 54 55 void work5() 56 { 57 int i; 58 for (i=1;i<=13;i++) 59 if (card[x][value[i]]) 60 break; 61 if (i!=14) 62 { 63 vis=0; 64 v++; 65 table[value[i]]++; 66 card[x][value[i]]--; 67 } 68 } 69 70 void fapai() 71 { 72 if (x==0) 73 { 74 if (card[x][y]) 75 work1(); 76 else 77 work2(); 78 } 79 else if (x==1) 80 { 81 if (card[x][y]) 82 work3(); 83 else 84 work2(); 85 } 86 else if (x==2) 87 { 88 if (card[x][y]) 89 work3(); 90 else 91 work4(); 92 } 93 else if (x==3) 94 { 95 if (card[x][y]>=3) 96 work3(); 97 else 98 { 99 work3(); 100 work5(); 101 } 102 } 103 } 104 105 bool faempty() 106 { 107 int i; 108 for (i=1;i<=13;i++) 109 if (card[x][i]!=0) 110 return 0; 111 return 1; 112 } 113 114 bool zhiyi(int index) 115 { 116 if (index==0) 117 { 118 if (index==(x+1)%4 && card[index][nexty]==0) 119 return 1; 120 if (v+card[index][y]>4) 121 return 1; 122 return 0; 123 } 124 else if (index==1) 125 { 126 if (index==(x+1)%4 && card[index][nexty]==0) 127 return 1; 128 return 0; 129 } 130 else if (index==2) 131 { 132 if (card[index][y]==4) 133 return 1; 134 return 0; 135 } 136 else 137 return faempty(); 138 } 139 140 void add(int index) 141 { 142 int i; 143 for (i=1;i<=13;i++) 144 { 145 card[index][i]+=table[i]; 146 table[i]=0; 147 } 148 } 149 150 void print() 151 { 152 int i,j,k; 153 for (i=0;i<4;i++) 154 { 155 vis=0; 156 for (j=1;j<=13;j++) 157 for (k=1;k<=card[i][j];k++) 158 { 159 if (vis) 160 printf(" "); 161 else 162 vis=1; 163 if (j==1) 164 printf("A"); 165 else if (j==10) 166 printf("10"); 167 else if (j==11) 168 printf("J"); 169 else if (j==12) 170 printf("Q"); 171 else if (j==13) 172 printf("K"); 173 else 174 printf("%c",j+48); 175 } 176 if (!vis) 177 printf("WINNER"); 178 printf(" "); 179 } 180 } 181 182 int main() 183 { 184 int i,j,index; 185 char ch[5]; 186 while (~scanf("%s",ch)) 187 { 188 memset(card,0,sizeof(card)); 189 memset(table,0,sizeof(table)); 190 for (i=0;i<4;i++) 191 { 192 for (j=1;j<=13;j++) 193 { 194 if (i!=0 || j!=1) 195 scanf("%s",ch); 196 if (ch[0]=='A') 197 card[i][1]++; 198 else if (ch[0]=='1') 199 card[i][10]++; 200 else if (ch[0]=='J') 201 card[i][11]++; 202 else if (ch[0]=='Q') 203 card[i][12]++; 204 else if (ch[0]=='K') 205 card[i][13]++; 206 else 207 card[i][ch[0]-48]++; 208 } 209 } 210 x=0; 211 y=1; 212 nexty=2; 213 while (1) 214 { 215 fapai(); 216 for (index=(x+1)%4;index!=x;index=(index+1)%4) 217 if (zhiyi(index)) 218 { 219 if (vis) 220 add(index); 221 else 222 add(x); 223 } 224 if (faempty()) 225 break; 226 // printf(" x=%d y=%d ",x,y); 227 // print(); 228 x=(x+1)%4; 229 y=nexty; 230 if (nexty==13) 231 nexty=1; 232 else 233 nexty++; 234 } 235 print(); 236 } 237 return 0; 238 }
莫名其妙单调队列代码没有做对，
思路：
对于i+1~i+n要满足任意前缀和大于等于0，
需满足 any x in [i+1,i+n] sum(x)-sum(i)>=0，
也就是求 min(sum(x))。
当然线段树求区间最小值，但就是太麻烦了。(网络有大佬是这样做的)
单调队列：
1 #include <cstdio> 2 #include <cstdlib> 3 #include <cmath> 4 #include <ctime> 5 #include <cstring> 6 #include <string> 7 #include <map> 8 #include <set> 9 #include <list> 10 #include <queue> 11 #include <stack> 12 #include <bitset> 13 #include <vector> 14 #include <algorithm> 15 #include <iostream> 16 using namespace std; 17 #define ll long long 18 const int maxn=1e6+10; 19 20 ll a[maxn<<1],tot[maxn<<1]; 21 int q[maxn<<1]; 22 23 int main() 24 { 25 int t,i,n,m,head,tail; 26 ll c,b; 27 scanf("%d",&t); 28 while (t--) 29 { 30 scanf("%d%lld",&n,&c); 31 for (i=1;i<=n;i++) 32 scanf("%lld",&a[i]); 33 for (i=1;i<=n;i++) 34 { 35 scanf("%lld",&b); 36 a[i]-=b; 37 } 38 for (i=n+1;i<2*n;i++) 39 a[i]=a[i-n]; 40 m=n<<1; 41 head=1; 42 tail=0; 43 tot[0]=0; 44 for (i=1;i<m;i++) 45 { 46 tot[i]=tot[i-1]+a[i]; 47 while (head<=tail && q[head]<=i-n) 48 head++; 49 while (tail>=head && tot[i]<tot[q[tail]]) 50 tail--; 51 tail++; 52 q[tail]=i; 53 if (i>=n && tot[q[head]]-tot[i-n]>=-c) 54 break; 55 } 56 if (i==m) 57 i=-1; 58 else 59 i-=n-1; 60 printf("%d ",i); 61 } 62 return 0; 63 } 64 /* 65 100 66 3 0 67 3 4 5 68 5 4 3 69 70 3 100 71 -3 -4 -5 72 30 40 50 73 74 3 1 75 1 5 4 76 2 3 1 77 78 5 3 79 1 2 3 4 100 80 2 4 5 10 5 81 82 5 0 83 1 2 3 4 5 84 2 3 2 5 3 85 86 1 1 87 3 88 4 89 90 5 0 91 5 1 2 4 3 92 3 2 4 5 1 93 */
当莫名奇妙很多人做对时，考虑一下贪心(找规律)，或者就是数据范围开小了
1 #include <bits/stdc++.h> 2 using namespace std; 3 #define ll long long 4 const int maxn=1e6; 5 6 ll a[maxn<<1],c; 7 int n; 8 9 bool judge(int j) 10 { 11 int i,k=j+n; 12 ll m=c; 13 for (i=j;i<k;i++) 14 { 15 m+=a[i]; 16 if (m<0) 17 return 0; 18 } 19 return 1; 20 } 21 22 int main() 23 { 24 int t,i; 25 ll b; 26 scanf("%d",&t); 27 while (t--) 28 { 29 scanf("%d%lld",&n,&c); 30 for (i=1;i<=n;i++) 31 scanf("%lld",&a[i]); 32 for (i=1;i<=n;i++) 33 { 34 scanf("%lld",&b); 35 a[i]-=b; 36 } 37 for (i=n+1;i<2*n;i++) 38 a[i]=a[i-n]; 39 for (i=1;i<=n;i++) 40 if (judge(i)) 41 break; 42 if (i==n+1) 43 i=-1; 44 printf("%d ",i); 45 } 46 return 0; 47 }
大佬的非常短的代码也看不懂(https://www.cnblogs.com/caomingpei/p/9691253.html)
写过的错误代码
https://paste.ubuntu.com/p/DkqyfqFXd6/