25 lines
No EOL
380 B
C++
25 lines
No EOL
380 B
C++
// pb_z5_15.cpp
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// Горбацевич Андрей
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#include <iostream>
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using namespace std;
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double ai(int);
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double s(int);
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int main() {
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int N;
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cout << "N >>>";
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cin >> N;
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cout << "S= " << ai(N);
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}
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double ai(int N) {
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double out = 0;
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for (int i = 1; i <= N; i++)
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out += i * s(i);
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return out;
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}
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double s(int i) {
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return (i % 2? -1 : 1);
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} |