Submission #706388

#	Time	Username	Problem	Language	Result	Execution time	Memory
706388		vjudge1	Balloons (CEOI11_bal)	C++11	20 / 100	153 ms	2016 KiB

bal

#include<iostream>
#include<vector>
using namespace std;
const long double absdiff = 0;
vector<pair<long double,long double> > curr;
int n;
long double findval(int pos, long double x) {
    return (curr[pos].first-x)*(curr[pos].first-x)/4.0/curr[pos].second;
}
bool isPoss(int pos, long double x) {
    if(pos <= 0) return true;
    if(pos >= curr.size()) return false;
    return (findval(pos,x)+absdiff < findval(pos-1,x));
}
int main () {
    scanf("%d",&n);
    for(int i = 0; i < n; i++) {
        long double x,rad;
        scanf("%Lf%Lf",&x,&rad);
        if(curr.size() > 0) {
            int l = -1, r = curr.size();
            while(l+1 < r) {
                int mid = (l+r)/2;
                if(isPoss(mid,x) == true) l = mid;
                else r = mid;
            }
            rad = min(rad,findval(l,x));
        }
        while(curr.size() > 0 && rad+absdiff > curr.back().second) {
            curr.pop_back();
        }
        curr.push_back(make_pair(x,rad));
        printf("%.3Lf\n",rad);
    }
    return 0;
}

Compilation message (stderr)

bal.cpp: In function 'bool isPoss(int, long double)':
bal.cpp:12:12: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long double, long double> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   12 |     if(pos >= curr.size()) return false;
      |        ~~~~^~~~~~~~~~~~~~
bal.cpp: In function 'int main()':
bal.cpp:16:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   16 |     scanf("%d",&n);
      |     ~~~~~^~~~~~~~~
bal.cpp:19:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   19 |         scanf("%Lf%Lf",&x,&rad);
      |         ~~~~~^~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 0 / 10
• Subtask 4: 0 / 10
• Subtask 5: 0 / 10
• Subtask 6: 0 / 10
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 10
• Subtask 10: 0 / 10