F - 食物链 POJ - 1182
作者:互联网
https://vjudge.net/contest/360957#problem/F
题解
https://blog.csdn.net/niushuai666/article/details/6981689
#include<iostream> #include<cstdio> #include<cstring> #include<algorithm> using namespace std; #define N 50010 struct node { int pre; int relation; }; node p[N]; int find(int x) //查找根结点 { if(x == p[x].pre) return x; int temp = p[x].pre; //路径压缩 p[x].pre = find(temp); p[x].relation = (p[x].relation + p[temp].relation) % 3; //关系域更新 return p[x].pre; //根结点 } int main() { int n, k; int ope, a, b; int root1, root2; int sum = 0; //假话数量 scanf("%d%d", &n, &k); for(int i = 1; i <= n; ++i) //初始化 { p[i].pre = i; p[i].relation = 0; } for(int i = 1; i <= k; ++i) { scanf("%d%d%d", &ope, &a, &b); if(a > n || b > n) //条件2 { sum++; continue; } if(ope == 2 && a == b) //条件3 { sum++; continue; } root1 = find(a); root2 = find(b); if(root1 != root2) // 合并 { p[root2].pre = root1; p[root2].relation = (3 + (ope - 1) +p[a].relation - p[b].relation) % 3; } else { if(ope == 1 && p[a].relation != p[b].relation) { sum++; continue; } if(ope == 2 && ((3 - p[a].relation + p[b].relation) % 3 != ope - 1)) { sum++; continue;} } } printf("%d\n", sum); return 0; }
标签:pre,食物链,int,sum,1182,ope,POJ,relation,root2 来源: https://www.cnblogs.com/SunChuangYu/p/12488964.html