Light OJ 1234 Harmonic Number Harmonic series section and

Source: Light OJ 1234 Harmonic Number

Question:

Train of Thought: no idea. This is a high number of things. When the divergence n is large enough, It is infinitely infinite and the formula is used to solve the problem.

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Using namespace std; const int maxn = 1000010; const double phi = 0.57721566490153286060651209; double a [maxn]; int main () {for (int I = 1; I <= 1000000; I ++) a [I] = a [I-1] + 1.0/I; int cas = 1; int T; scanf ("% d", & T ); while (T --) {int n; scanf ("% d", & n); double ans; if (n <= 1000000) ans = a [n]; elseans = log (n + 0.5) + phi; printf ("Case % d: %. 10lf \ n ", cas ++, ans);} return 0 ;}