题解:尼姆博弈,SG(i)=i,要使当前堆可取,则数量必须大于其余所有堆的SG异或值,这样才可以减到其SG值使总异或值为0,又不可不取,所以不能取等号。
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#include <cstdio> using
namespace std;
int SG[105];
int main(){
int
n,sum,cnt,i;
while
( scanf ( "%d" ,&n),n){
sum=cnt=0;
for (i=0;i<n;i++) scanf ( "%d" ,&SG[i]),sum^=SG[i];
for (i=0;i<n;i++){sum^=SG[i]; if (SG[i]>sum)cnt++;sum^=SG[i];}
printf ( "%d\n" ,cnt);
}
return
0;
} |