rt,一开始这样是无法运行的(vscode+devcpp)

#include <bits/stdc++.h>
using namespace std;
#define int long long
inline int read()
{
    int res = 0, f = 1;
    char ch = getchar();
    while (ch < '0' || ch > '9')
    {
        if (ch == '-')
            f = -1;
        ch = getchar();
    }
    while (ch >= '0' && ch <= '9')
        res = res * 10 + ch - 48, ch = getchar();
    return res * f;
}
const int maxn = 505;
const int maxm = 1000005;
int num[maxm];
int n, m, s, t, e, cnt;
struct mat
{
    int a[maxn][maxn];
    // inline mat() { memset(a, 0, sizeof a); }
    inline mat operator*(const mat &b) const
    {
        mat c;
        memset(c.a, 0x3f, sizeof c.a);
        for (register int k = 1; k <= cnt; ++k)
            for (register int i = 1; i <= cnt; ++i)
                for (register int j = 1; j <= cnt; ++j)
                    c.a[i][j] = min(c.a[i][j], a[i][k] + b.a[k][j]);
        return c;
    }
} dis, ans;
inline mat qpow(mat a, int b)
{
    mat res=a;
    b--;
    while (b)
    {
        if (b & 1)
            res = res * a;
        a = a * a;
        b >>= 1;
    }
    return res;
}
inline void mem()
{
    memset(dis.a, 0x3f, sizeof dis.a);
    n = read();
    t = read();
    s = read();
    e = read();
    for (register int i = 1, x, y, z; i <= t; ++i)
    {
        x = read();
        y = read();
        z = read();
        if (!num[y])
            num[y] = ++cnt;
        if (!num[z])
            num[z] = ++cnt;
        dis.a[num[y]][num[z]] = dis.a[num[z]][num[y]] = x;
    }
    return;
}
signed main()
{
    mem();
    ans = qpow(dis, n);
    cout << ans.a[num[s]][num[e]];
}

dev返回3开头的一个大数

#include <bits/stdc++.h>
using namespace std;
#define int long long
inline int read()
{
    int res = 0, f = 1;
    char ch = getchar();
    while (ch < '0' || ch > '9')
    {
        if (ch == '-')
            f = -1;
        ch = getchar();
    }
    while (ch >= '0' && ch <= '9')
        res = res * 10 + ch - 48, ch = getchar();
    return res * f;
}
const int maxn = 505;
const int maxm = 1000005;
int num[maxm];
int n, m, s, t, e, cnt;
struct mat
{
    int a[maxn][maxn];
    // inline mat() { memset(a, 0, sizeof a); }
    inline mat operator*(const mat &b) const
    {
        mat c;
        memset(c.a, 0x3f, sizeof c.a);
        for (register int k = 1; k <= cnt; ++k)
            for (register int i = 1; i <= cnt; ++i)
                for (register int j = 1; j <= cnt; ++j)
                    c.a[i][j] = min(c.a[i][j], a[i][k] + b.a[k][j]);
        return c;
    }
} dis, ans;
inline void qpow(int b)
{
    while (b)
    {
        if (b & 1)
            ans = ans * dis;
        dis = dis * dis;
        b >>= 1;
    }
    return ;
}
inline void mem()
{
    memset(dis.a, 0x3f, sizeof dis.a);
    n = read();
    t = read();
    s = read();
    e = read();
    for (register int i = 1, x, y, z; i <= t; ++i)
    {
        x = read();
        y = read();
        z = read();
        if (!num[y])
            num[y] = ++cnt;
        if (!num[z])
            num[z] = ++cnt;
        dis.a[num[y]][num[z]] = dis.a[num[z]][num[y]] = x;
    }
    return;
}
signed main()
{
    mem();
    ans = dis;
    qpow(n - 1);
    cout << ans.a[num[s]][num[e]];
}

这样本地可运行 而这样本地也无法运行并提交AC

inline mat qpow(int b)
{
    mat res=dis;
    mat a=dis;
    b--;
    while (b)
    {
        if (b & 1)
            res = res * a;
        a = a * a;
        b >>= 1;
    }
    return res;
}

而且以前写矩阵快速幂的时候这样也没事 请问这是啥原因(数组不大呀)