Submission #91785

# Submission time Handle Problem Language Result Execution time Memory
91785 2018-12-30T02:49:22 Z updown1 Mobile (BOI12_mobile) C++17
21 / 100
1000 ms 29992 KB
/*
binary search on the answer
to test a value x, for all the circles come up with ranges of the line that is covered if the circle has a radius x
find the minimum value x s.t. the whole line is covered
*/
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define For(i, a, b) for(int i=a; i<b; i++)
#define ffi For(i, 0, N)
#define ffj For(j, 0, N)
#define ffa ffi ffj
#define s <<" "<<
#define c <<" : "<<
#define w cout
#define e endl//"\n"
#define pb push_back
#define mp make_pair
#define a first
#define b second
#define int ll
//#define double long double
const int MAXN=1000000, INF=1000000000000000000;
///500,000,000
int N, L;
pair<double, double> pts[MAXN], rng[MAXN];

double sqrt1(long double x) {
    double a = 0, b = x;
    while (b-a > .001) {
        double mid = (a+b)/2;
        if (mid*mid > x) b = mid;
        else a = mid;
    }
    return a;
}

bool full(double rr) {
    /// make the ranges
    ffi {
        int x = pts[i].a, y = pts[i].b;
        if (y*y > rr*rr) {rng[i] = mp(0, 0); continue;}
        double a = sqrt1((long double)rr*rr-y*y);
        double l = x - a; double r = x + a;
        l = max(l, (double) 0); l = min(l, (double)L);
        r = max(r, (double) 0); r = min(r, (double)L);
        rng[i] = mp(l, r);
    }
    //exit(0);
    sort(rng, rng+N);
    //w<< rr<<e; ffi w<< rng[i].a s rng[i].b<<e;
    /// see if the whole range is covered
    double far = 0;
    ffi {
        if (rng[i].a > far) return false;
        far = max(far, rng[i].b);
    }
    return far >=L;
}

main() {
    //ifstream cin("test.in");
	ios_base::sync_with_stdio(0); cin.tie(0);
	cin >> N >> L;
	double a = 2236067978, b = 2236067978;
	ffi {
	    cin >> pts[i].a >> pts[i].b;
	    double x = pts[i].a, y = pts[i].b;
	    double use1 = sqrt1((long double)x*x+y*y);
	    double use2 = sqrt1((long double)(x-L)*(x-L)+y*y);
	    b = min(b, max(use1, use2));
	    a = min(a, min(use1, use2));
	}
	while (b-a > .001) {
        double mid = (a+b)/2;
        if (full(mid)) b = mid;
        else a = mid;
	}
	w<< fixed << setprecision(4) <<a<<e;
}

Compilation message

mobile.cpp:61:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main() {
      ^
# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 2 ms 376 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 2 ms 376 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 5 ms 376 KB Output is correct
2 Correct 7 ms 504 KB Output is correct
3 Correct 4 ms 376 KB Output is correct
4 Correct 55 ms 468 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 9 ms 504 KB Output is correct
2 Correct 42 ms 504 KB Output is correct
3 Incorrect 20 ms 504 KB Output isn't correct
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 10 ms 508 KB Output is correct
2 Correct 42 ms 504 KB Output is correct
3 Correct 16 ms 504 KB Output is correct
4 Correct 12 ms 504 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 23 ms 504 KB Output is correct
2 Correct 44 ms 552 KB Output is correct
3 Incorrect 21 ms 504 KB Output isn't correct
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 351 ms 2680 KB Output is correct
2 Incorrect 949 ms 2808 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 125 ms 2808 KB Output is correct
2 Correct 130 ms 2492 KB Output is correct
3 Correct 161 ms 2964 KB Output is correct
4 Correct 178 ms 2764 KB Output is correct
5 Correct 215 ms 3192 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 424 ms 3136 KB Output is correct
2 Execution timed out 1042 ms 3064 KB Time limit exceeded
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Execution timed out 1083 ms 3448 KB Time limit exceeded
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Execution timed out 1071 ms 3448 KB Time limit exceeded
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Execution timed out 1076 ms 16036 KB Time limit exceeded
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Execution timed out 1080 ms 16092 KB Time limit exceeded
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Execution timed out 1072 ms 19316 KB Time limit exceeded
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Execution timed out 1064 ms 19132 KB Time limit exceeded
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Execution timed out 1075 ms 22308 KB Time limit exceeded
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Execution timed out 1083 ms 22392 KB Time limit exceeded
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Execution timed out 1083 ms 25596 KB Time limit exceeded
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Execution timed out 1083 ms 19608 KB Time limit exceeded
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Execution timed out 1080 ms 29992 KB Time limit exceeded
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Execution timed out 1081 ms 14672 KB Time limit exceeded
2 Halted 0 ms 0 KB -