Throwing Dice LightOJ-1064 | | (Barely available) fractional class

Throwing Dice LightOJ-1064

Method:

Set ANS[I][J] Indicates the probability that I have a dice point that is exactly J. Then ans[1][1] to ans[1][6] are 1/6.

Apparently, $ans [i][j]=sum\{ans[i-1][j-k]\} (1<=K<=6,J>K) $

The upper limit of N and X is very small, directly processing the result of all the points exactly a certain value, and then do again like the prefix and things to deal with all points greater than or equal to a value of the result. Here the answer needs a score, so we write a fractional structure.

Fractional operations (not optimized):

Initialize empty score: Numerator is 0, denominator is 1

Addition:-Pass first, then add molecule, then numerator

Multiplication: Numerator each other first, then multiplying the numerator by the denominator

Error number: 1 times

Error reason: Because the prefix and the scope limit of the original data is mixed, 66 lines >=0 written >=i, resulting in WA

1#include <cstdio>2typedefLong LongLL;3 ll gcd (ll A,ll b)4 {5 LL t;6      while(b!=0)7     {8t=A;9A=b;Tenb=t%b; One     } A     returnA; - } - structX the { - LL A, b; - X () -     { +A=0; b=1; -     } +XintXinty) A     { ata=x;b=y; -     } -Xoperator+(Constx&c) -     { - X ans; -LL tmp=gcd (B,C.B); inans.b=b/tmp*c.b; -ans.a=ans.b/b*a+ans.b/c.b*C.A; totmp=gcd (ans.a,ans.b); +Ans.a/=tmp; -Ans.b/=tmp; the         returnans; *     } $Xoperator*(Constx&c)Panax Notoginseng     { -LL TMP1=GCD (a,c.b), tmp2=gcd (B,C.A); the X ans; +ans.a=a/tmp1*c.a/TMP2; Aans.b=b/tmp2*c.b/Tmp1; the         returnans; +     } -     voidprint () $     { $         if(b==1) -printf"%lld", a); -         Else theprintf"%lld/%lld", A, b); -     }Wuyi}ans[ -][151],ans2[ -][151]; the LL t,tt,n,x; - intMain () Wu { -     inti,j,k; About      for(i=1; i<=6; i++) $ans[1][i]= (X) {1,6}; -      for(i=2; i<= -; i++) -          for(j=i;j<=6*i;j++) -              for(k=1; k<=6; k++) A                 if(j-k>0) +ans[i][j]=ans[i][j]+ans[i-1][j-k]*ans[1][1];//ans[1][1] is 1/6 the      for(i=1; i<= -; i++) -     { $ans2[i][6*i]=ans[i][6*i]; the          for(j=6*i-1; j>=0; j--) theans2[i][j]=ans2[i][j+1]+Ans[i][j]; the     } thescanf"%lld",&T); -      for(tt=1; tt<=t;tt++) in     { thescanf"%lld%lld",&n,&x); theprintf"Case %LLD:", TT); About ans2[n][x].print (); thePuts""); the     } the     return 0; +}

Throwing Dice LightOJ-1064 | | (Barely available) fractional class