/* このコード、と~おれ! Be accepted! ∧_∧  (。・ω・。)つ━☆・*。 ⊂   ノ    ・゜+.  しーJ   °。+ *´¨)          .· ´¸.·*´¨) ¸.·*¨)           (¸.·´ (¸.·'* ☆ */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* 多倍長整数, cpp_intで宣言 #include using namespace boost::multiprecision; */ //#pragma gcc target ("avx2") //#pragma gcc optimization ("o3") //#pragma gcc optimization ("unroll-loops") #define rep(i, n) for(int i = 0; i < (n); ++i) #define rep1(i, n) for(int i = 1; i <= (n); ++i) #define rep2(i, n) for(int i = 2; i < (n); ++i) #define repr(i, n) for(int i = n; i >= 0; --i) #define reprm(i, n) for(int i = n - 1; i >= 0; --i) #define printynl(a) printf(a ? "yes\n" : "no\n") #define printyn(a) printf(a ? "Yes\n" : "No\n") #define printYN(a) printf(a ? "YES\n" : "NO\n") #define printim(a) printf(a ? "possible\n" : "imposible\n") #define printdb(a) printf("%.50lf\n", a) //少数出力 #define printLdb(a) printf("%.50Lf\n", a) //少数出力 #define printdbd(a) printf("%.16lf\n", a) //少数出力(桁少なめ) #define prints(s) printf("%s\n", s.c_str()) //string出力 #define all(x) (x).begin(), (x).end() #define allsum(a, b, c) ((a + b) * c / 2LL) //等差数列の和、初項,末項,項数 #define pb push_back #define rpriq priq, greater> #define deg_to_rad(deg) (((deg)/360.0L)*2.0L*PI) #define rad_to_deg(rad) (((rad)/2.0L/PI)*360.0L) #define Please return #define AC 0 #define manhattan_dist(a, b, c, d) (abs(a - c) + abs(b - d)) /*(a, b) から (c, d) のマンハッタン距離 */ #define inf numeric_limits::infinity(); #define linf numeric_limits::infinity() using ll = long long; constexpr int INF = 1073741823; constexpr int MINF = -1073741823; constexpr ll LINF = ll(4661686018427387903); constexpr ll MOD = 1000000007; constexpr long double eps = 1e-9; const long double PI = acosl(-1.0L); using namespace std; void scans(string& str) { char c; str = ""; scanf("%c", &c); if (c == '\n')scanf("%c", &c); while (c != '\n' && c != -1 && c != ' ') { str += c; scanf("%c", &c); } } void scanc(char& str) { char c; scanf("%c", &c); if (c == -1)return; while (c == '\n') { scanf("%c", &c); } str = c; } double acot(double x) { return PI / 2 - atan(x); } ll LSB(ll n) { return (n & (-n)); } /*-----------------------------------------ここからコード-----------------------------------------*/ int main() { ll l, r; scanf("%lld%lld", &l, &r); vector b(r * 2 + 1); ll ans = 0; for (ll i = l; i <= r; ++i) { for (ll j = i * 2; j <= r; j += i)b[j] = true; } for (ll i = l; i <= r; ++i) { if (not b[i])++ans; } printf("%lld\n", ans - 1); Please AC; }