http://acm.pku.edu.cn/JudgeOnline/problem?id=1218
Код:
#include <stdio.h> int main() { int T,n; int i,j; scanf("%d", &T); while(T--) { int cnt=0; int cell[101]={0,}; scanf("%d", &n); for(i=1;i<=n;i++) { for(j=i;j<=n;j+=i) { cell[j] = !cell[j]; } } for(i=1;i<=n;i++) if(cell[i]) cnt++; printf("%d\n", cnt); } return 0; }