61 lines
1.3 KiB
C++
61 lines
1.3 KiB
C++
#include <iostream>
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constexpr int MAX_N = 1e6 + 1;
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int n, ans = 0;
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int values[MAX_N], sums[MAX_N], min_sums[2][MAX_N];
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void init_sums() {
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sums[0] = values[0];
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for (int i = 1; i < n; i++) {
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sums[i] = sums[i - 1] + values[i];
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}
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}
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void init_min_sums() {
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min_sums[0][0] = sums[0];
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for (int i = 1; i < n; i++) {
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min_sums[0][i] = std::min(min_sums[0][i - 1], sums[i]);
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}
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min_sums[1][n - 1] = sums[n - 1];
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for (int i = n - 2; i >= 0; i--) {
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min_sums[1][i] = std::min(min_sums[1][i + 1], sums[i]);
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}
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}
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int main() {
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std::ios::sync_with_stdio(false);
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std::cin.tie(nullptr);
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std::cin >> n;
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for (int i = 0; i < n; i++) {
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std::cin >> values[i];
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}
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init_sums();
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init_min_sums();
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for (int i = 0; i < n - 1; i++) {
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int delta1 = sums[i];
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int delta2 = sums[n - 1] - sums[i];
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if (min_sums[0][i] + delta2 >= 0 && min_sums[1][i + 1] - delta1 >= 0) {
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std::clog << i << std::endl;
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ans++;
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}
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}
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bool flag = false;
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for (int i = 0; i < n; i++) {
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if (sums[i] < 0) {
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flag = true;
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break;
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}
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}
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if (!flag) {
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std::clog << n - 1 << std::endl;
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ans++;
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}
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std::cout << ans << std::endl;
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return 0;
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}
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