P2249满江红求调，几乎复制题解但全WA

P2249 【深基13.例1】查找

PAS_ @ 2023-07-17 21:25:31

这是帮一个禁言的朋友问的

参考了第一篇题解的代码

题解代码能AC

这几乎可以说是从题解修改来的代码：

#include <bits/stdc++.h>
#define int long long
using namespace std;
const int MAXN=1e6+10;
int a[MAXN];
int fastread(){
    int x=0,y=1;
    char ch=getchar();
    while (ch<'0'||ch>'9'){
        if (ch=='-')
            y=-1;
        ch=getchar();
    }
    return x*y;
}
signed main(){
    int n=fastread(),m=fastread();
    for (int i=1;i<=n;i++){
        a[i]=fastread();
    }
    while (m--){
        int x=fastread(),ans=lower_bound(a+1,a+n+1,x)-a;
        if (x!=a[ans]) 
            cout<<"-1";
        else
            cout<<ans;
    }
    return 0; 
}

WA了

orz求教

by 2011FYCCCTA @ 2023-07-17 21:28:18

空格呢？

by 2011FYCCCTA @ 2023-07-17 21:29:05

每次输出后都要有空格

by 2011FYCCCTA @ 2023-07-17 21:29:56

@PAS_

by sandwich03 @ 2023-07-17 21:31:27

我想知道你int fastread()干什么的？x一直为0。x*y也为0？

by sandwich03 @ 2023-07-17 21:33:07

@PAS_ 我是说你fastread()的返回值一直为0

by PAS_ @ 2023-07-17 21:38:00

@linzhi123 快读（虽然可能效果不大？

by PAS_ @ 2023-07-17 21:38:13

@2011FYCCCTA thx

by PAS_ @ 2023-07-17 21:47:43

@2011FYCCCTA

srds咋又WA了

#include <bits/stdc++.h>
#define int long long
using namespace std;
const int MAXN=1e6+10;
int a[MAXN];
int fastread(){
    int x=0,y=1;
    char ch=getchar();
    while (ch<'0'||ch>'9'){
        if (ch=='-')
            y=-1;
        ch=getchar();
    }
    return x*y;
}
signed main(){
    int n=fastread(),m=fastread();
    for (int i=1;i<=n;i++){
        a[i]=fastread();
    }
    while (m--){
        int x=fastread(),ans=lower_bound(a+1,a+n+1,x)-a;
        if (x!=a[ans]) 
            cout<<"-1 ";
        else
            cout<<ans<<" ";
    }
    return 0; 
}

by 2011FYCCCTA @ 2023-07-18 06:05:47

@PAS_ 看我楼下，你快读写错了

|