【洛谷P1795 无穷的序列_NOI导刊2010提高（05）】模拟

分析

map搞一下

AC代码

#include <bits/stdc++.h>
using namespace std;
map<int,int> mp;
inline int read() {
    int w=0,x=0; char ch=0;
    while (!isdigit(ch)) {w|=ch=='-';ch=getchar();}
    while (isdigit(ch)) {x=(x<<1)+(x<<3)+(ch^48);ch=getchar();}
    return w?-x:x;
}
int main() {
    int sum=1;
    for (int i=0;i<=100000;i++) {
        sum+=i;
        mp[sum]=i;
        if (sum>1e9) break;
    }
    int n=read();
    while (n--) {
        int x=read();
        if (mp.count(x)) printf("1\n");
        else printf("0\n");
    }
    return 0;
}