[KOI]전국본선 2013 중등부 첫번째 문제

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#include <stdio.h> #include <algorithm> #include <vector> using namespace std;   struct ANIMAL {     int y, x; };   vector<int> hunter; vector<animal> animal;   bool comp(const ANIMAL& a, const ANIMAL& b) {     return (a.x < b.x); }   bool is_kill(const ANIMAL& a, const int h, const int len) {     int dist = abs(a.x - h) + a.y;     if (dist <= len)     return true;     else                    return false; }   int main() {     int M, N, L;     scanf("%d %d %d", &M, &N, &L);       hunter.resize(M);     animal.resize(N);       for (int i = 0; i < M; ++i) {         scanf("%d", &hunter[i]);     }       for (int i = 0; i < N; ++i) {         scanf("%d %d", &animal[i].x, &animal[i].y);     }       sort(hunter.begin(), hunter.end());     sort(animal.begin(), animal.end(), comp);       int ret = 0;     for (auto ani : animal) {         auto target = lower_bound(hunter.begin(), hunter.end(), ani.x) - hunter.begin();         if (is_kill(ani, hunter[target], L)) {             ++ret;         }         else {             if (target > 0) {                 --target;                 if (is_kill(ani, hunter[target], L)) {                     ++ret;                 }             }         }     }       printf("%d\n", ret);           return 0; }