Sicily 1444:prime Path (BFS)

　　Test instructions to give two four-bit primes A, B, each time only a certain number of a can be modified to make it another four-bit prime, ask at least how many operations, can make a change to B. BFS search can be done directly

1#include <bits/stdc++.h>2 using namespacestd;3 4 BOOLIsPrime (intN) {//Prime Judgment5     if(n = =2|| n = =3)return true;6     Else{7         intK = sqrt (n) +1;8          for(inti =2; I < K; i++){9             if(n% i = =0)return false;Ten         } One         return true; A     } - } -  the BOOLprime[10010];  - intvisit[10010]; - voidGetprime () { -      for(inti = +; I <10000; i++){ +         if(IsPrime (i)) Prime[i] =true; -     } + } A  at structnode{ -     intNum//Storing numbers -     intCost//number of operation steps - };  -  -Node BFS (intStartintend) { inQueue<node>Q; - Node Front; toFront.num =start; +Front.cost =0; -Visit[start] =1; the Q.push (front); *      while(!Q.empty ()) { $Front =Q.front (); Q.pop ();Panax Notoginseng          -          for(inti =1; I <Ten; i++) {//Change thousands the             intm =Front.num; +m = m% ++ I * +; A             if(!visit[m] &&Prime[m]) { theVISIT[M] =1;  +Node tmp =Front; -Tmp.num =m; $tmp.cost++; $ Q.push (TMP); -                  -                 if(m = = end)returntmp; the             } -         }Wuyi          the          for(inti =0; I <Ten; i++) {//change the Hundred . -             intm =Front.num; Wum = m% -+ (m/ +) * ++ I * -; -             if(!visit[m] &&Prime[m]) { AboutVISIT[M] =1;  $Node tmp =Front; -Tmp.num =m; -tmp.cost++; - Q.push (TMP); A                  +                 if(m = = end)returntmp; the             } -         } $          the          for(inti =0; I <Ten; i++) {//Change 10 bit the             intm =Front.num; them = m%Ten+ (m/ -) * -+ I *Ten; the             if(!visit[m] &&Prime[m]) { -VISIT[M] =1;  inNode tmp =Front; theTmp.num =m; thetmp.cost++; About Q.push (TMP); the                 if(m = = end)returntmp; the             } the         } +          -          for(inti =0; I <Ten; i++) {//Change Bits the             intm =Front.num;Bayim = (m/Ten) *Ten+i; the             if(!visit[m] &&Prime[m]) { theVISIT[M] =1;  -Node tmp =Front; -Tmp.num =m; thetmp.cost++; the Q.push (TMP); the                  the                 if(m = = end)returntmp; -             } the         } the     } the Node tmp;94Tmp.num =0; theTmp.cost =0; the     returntmp; the }98 intMain () { About     intN; -CIN >>N;101 getprime ();102      while(n--){103         intA, B;104Cin >> a >>b; the Node tmp;106memset (Visit,0,sizeof(visit));107TMP =BFS (A, b);108         if(Tmp.num = =0&& Tmp.cost = =0) cout <<0<<Endl;109         Else{ thecout << tmp.cost <<Endl;111         } the     } 113}

Sicily 1444:prime Path (BFS)