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43 lines
744 B
C++
43 lines
744 B
C++
#include <iostream>
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#include <fstream>
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#include <map>
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#include <numeric>
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// using std::cin;
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// using std::cout;
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std::ifstream cin("segment.in");
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std::ofstream cout("segment.out");
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const char endl = '\n';
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const int N = 5e5 + 5;
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const int mod = 1e9 + 7;
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int n;
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long long a[N], s[N], f[N], sum;
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std::map<long long, long long> map;
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int main() {
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std::ios::sync_with_stdio(false);
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cin.tie(nullptr);
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cin >> n;
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for (int i = 1; i <= n; i++) {
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cin >> a[i];
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}
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std::partial_sum(a + 1, a + 1 + n, s + 1);
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f[0] = sum = 1;
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for (int i = 1; i <= n; i++) {
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f[i] = sum;
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sum = ((sum + f[i] - map[s[i]]) % mod + mod) % mod;
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map[s[i]] = f[i];
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}
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cout << f[n] << endl;
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return 0;
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}
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