字典树,注意释放内存,否则MLE
#include<iostream> #include<cstring> #include<cstdio> using namespace std; char a[10010][20]; struct node { int num; node *childs[10]; node() { num = 0; for(int i = 0; i < 10; i++) childs[i] = NULL; } }; node *root = new node; node *nownode,*newnode; void Insert(char *str) { nownode = root; int lens = strlen(str); for(int i = 0; i < lens; i++) { int m = str[i] - '0'; if(nownode->childs[m] != NULL) { nownode = nownode->childs[m]; nownode->num++; } else { newnode = new node; ++newnode->num; nownode->childs[m] = newnode; nownode = nownode->childs[m]; } } } int Find(char *str) { nownode = root; int lens = strlen(str); for(int i = 0; i < lens; i++) { int m = str[i] - '0'; nownode = nownode->childs[m]; } return nownode->num; } void del(node *root) { for(int i=0; i<10; i++) { if(root->childs[i]!=NULL) { del(root->childs[i]); } } delete(root); } int main() { int t; scanf("%d",&t); while(t--) { int n; root = new node; scanf("%d",&n); for(int i = 0; i < n; i++) { scanf("%s",a[i]); Insert(a[i]); } bool flag = true; for(int i = 0; i < n; i++) { if(Find(a[i]) != 1) { flag = false; break; } } if(flag)puts("YES"); else puts("NO"); del(root); } return 0; }