为什么本地能运行，洛谷上跑却CE了

CodeAtlantis @ 2022-07-08 23:08:14

#include<bits/stdc++.h>
using namespace std;

int main(){
    char a1[2005], b1[2005];
    int a[2005], b[2005], c[2005];
    int lena, lenb, lenc, x;
    memset(a, 0, sizeof(a));     
    memset(b, 0, sizeof(b));     
    memset(c, 0, sizeof(c));
    gets(a1);gets(b1);
    lena = strlen(a1);lenb = strlen(b1);     
    for(int i = 0; i <= lena-1; i++)
        a[lena-i] = a1[i] - 48;
    for(int i = 0; i <= lenb-1; i++)
        b[lenb-i] = b1[i] - 48;
    for(int i = 1; i <= lena; i++){
        x = 0;
        for(int j = 1; j <= lenb; j++){
            c[i+j-1]=a[i]*b[j]+x+c[i+j-1];//
            x=c[i+j-1]/10;
            c[i+j-1]%=10;
        }
        c[i+lenb]=x;
    }
    lenc = lena + lenb;
    while(c[lenc]==0&&lenc>1)
        lenc--;
    for(int i = lenc; i >= 1; i--)
        cout << c[i];
    cout << endl;
    return 0;
}

by Lunar_Hjj @ 2022-07-08 23:16:37

gets()的问题，洛谷上交不了的

by Lunar_Hjj @ 2022-07-08 23:19:07

编译信息节选：‘gets’ was not declared in this scope;

翻译：在此作用域中gets未定义

by harvey2019 @ 2022-07-08 23:40:17

gets ……

by Coros_Trusds @ 2022-07-09 07:25:55

#include<bits/stdc++.h>
using namespace std;

int main(){
    char a1[2005], b1[2005];
    int a[2005], b[2005], c[2005];
    int lena, lenb, lenc, x;
    memset(a, 0, sizeof(a));     
    memset(b, 0, sizeof(b));     
    memset(c, 0, sizeof(c));
    fgets(a1,2005,stdin);fgets(b1,2005,stdin);
    lena = strlen(a1);lenb = strlen(b1);     
    for(int i = 0; i <= lena-1; i++)
        a[lena-i] = a1[i] - 48;
    for(int i = 0; i <= lenb-1; i++)
        b[lenb-i] = b1[i] - 48;
    for(int i = 1; i <= lena; i++){
        x = 0;
        for(int j = 1; j <= lenb; j++){
            c[i+j-1]=a[i]*b[j]+x+c[i+j-1];//
            x=c[i+j-1]/10;
            c[i+j-1]%=10;
        }
        c[i+lenb]=x;
    }
    lenc = lena + lenb;
    while(c[lenc]==0&&lenc>1)
        lenc--;
    for(int i = lenc; i >= 1; i--)
        cout << c[i];
    cout << endl;
    return 0;
}

by Coros_Trusds @ 2022-07-09 07:26:40

你应该写错了

by CodeAtlantis @ 2022-07-09 19:23:38

@Coros_Trusds 谢谢大佬指教

by CodeAtlantis @ 2022-07-09 19:27:46

@Coros_Trusds

大佬 改成这个全WA了https://www.luogu.com.cn/record/78912107

自己用cin输入却只有最后一个点WA https://www.luogu.com.cn/record/78911767

by Coros_Trusds @ 2022-07-09 20:42:56

@极客666 抱歉原因是 fgets 读入会把换行符 \n 也一起读入导致奇奇怪怪的错误

仔细看了下你的数组开小了

AC 代码：

#include<bits/stdc++.h>
using namespace std;

const int N = 4e4 + 5;
char a1[N], b1[N];
int a[N], b[N], c[N];
int main(){

    int lena, lenb, lenc, x;
    memset(a, 0, sizeof(a));     
    memset(b, 0, sizeof(b));     
    memset(c, 0, sizeof(c));
    cin >> a1 >> b1;
    lena = strlen(a1);lenb = strlen(b1);     
    for(int i = 0; i <= lena-1; i++)
        a[lena-i] = a1[i] - 48;
    for(int i = 0; i <= lenb-1; i++)
        b[lenb-i] = b1[i] - 48;
    for(int i = 1; i <= lena; i++){
        x = 0;
        for(int j = 1; j <= lenb; j++){
            c[i+j-1]=a[i]*b[j]+x+c[i+j-1];//
            x=c[i+j-1]/10;
            c[i+j-1]%=10;
        }
        c[i+lenb]=x;
    }
    lenc = lena + lenb;
    while(c[lenc]==0&&lenc>1)
        lenc--;
    for(int i = lenc; i >= 1; i--)
        cout << c[i];
    cout << endl;
    return 0;
}

by CodeAtlantis @ 2022-07-09 22:07:14

@Coros_Trusds 太感谢了