Submission #133114

# Submission time Handle Problem Language Result Execution time Memory
133114 2019-07-20T07:40:43 Z win11905 Mobile (BOI12_mobile) C++11
0 / 100
257 ms 20588 KB
#include <bits/stdc++.h>
#define pii pair<int, int>
#define x first
#define y second
using namespace std;

int n, k;
vector<pii> vec;

double dist(pii p, double x) {
    return hypot((double)p.x - x, (double)p.y);
}

double f(double x) { return x * x; }

double getx(pii p1, pii p2) {
    double x1 = p1.x, x2 = p2.x, y1 = p1.y, y2 = p2.y;
    return (f(x2) + f(y2) - f(x1) - f(y1)) / (2 * (x2 - x1));
}

int main() {
    scanf("%d %d", &n, &k);
    for(int i = 0, x, y; i < n; ++i) {
        scanf("%d %d", &x, &y);
        if(vec.empty()) vec.emplace_back(x, abs(y));
        else if(vec.back().x == x) vec.back().y = min(vec.back().y, abs(y));
        else vec.emplace_back(x, abs(y));
    }
    vector<pii> stk;
    stk.emplace_back(vec[0]), stk.emplace_back(vec[1]);
    for(int i = 2; i < vec.size(); ++i) {
        while(stk.size() >= 2 && getx(stk.back(), stk[stk.size()-2]) > getx(stk[stk.size()-2], vec[i])) stk.pop_back();
        stk.emplace_back(vec[i]);
    }
    double ans = 1e18;
    for(int i = 1; i < vec.size(); ++i) {
        double x = getx(vec[i], vec[i-1]);
        if(x >= 0 && x <= k) {
            ans = min(ans, dist(vec[i], x));
        }
    }
    printf("%.6f\n", ans);
}

Compilation message

mobile.cpp: In function 'int main()':
mobile.cpp:31:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 2; i < vec.size(); ++i) {
                    ~~^~~~~~~~~~~~
mobile.cpp:36:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 1; i < vec.size(); ++i) {
                    ~~^~~~~~~~~~~~
mobile.cpp:22:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d", &n, &k);
     ~~~~~^~~~~~~~~~~~~~~~~
mobile.cpp:24:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d %d", &x, &y);
         ~~~~~^~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 256 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 376 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 380 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 3 ms 376 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 3 ms 376 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 3 ms 376 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 22 ms 1520 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 18 ms 376 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 23 ms 2536 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 30 ms 1140 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 34 ms 2056 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 126 ms 10408 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 131 ms 552 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 155 ms 17384 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 157 ms 460 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 179 ms 18080 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 182 ms 516 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 202 ms 18936 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 213 ms 460 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 251 ms 20588 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 257 ms 536 KB Output isn't correct
2 Halted 0 ms 0 KB -