注意事项：无。

代码：

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int n, m;
bool a[MAXn + 10][MAXm + 10];
int guass() {
    int row = 1, mxchoser = 0;
    for (int col = 1; col <= m && row <= n; ++col) {
        int choser = -1;
        for (int i = row; i <= n; ++i) {
            if (a[i][col]) {
                choser = i;
                break;
            }
        }
        if (choser == -1) continue;
        mxchoser = max(mxchoser, choser);
        if (choser != row) swap(a[row], a[choser]);
        for (int i = 1; i <= n; ++i) {
            if (i == row) continue;
            if (a[i][col]) {
                for (int j = col; j <= m + 1; ++j) {
                    a[i][j] ^= a[row][j];
                }
            }
        }
        ++row;
    }
    bool noans = 0, moreans = 0;
    if (row <= m) {
        for (int i = row; i <= n; ++i) {
            if (a[i][m + 1]) {
                noans = 1;
                break;
            }
        }
        if (noans == 0) moreans = 1;
    }
    if (noans) return 0;
    else if (moreans) return -1;
    else return mxchoser;
}

Luogu P2447 [SDOI2010] 外星千足虫

代码（本代码中 nn 和 mm 和题面中的是反的，代码中 nn 代表矩阵的行数，mm 代表列数）：

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#include<bits/stdc++.h>
using namespace std;
const int MAXn = 2e3;
const int MAXm = 1e3;

template <typename T>
inline void read(T &a) {
    char c;for (c = getchar(); (c < '0' || c > '9') && c != '-'; c = getchar());bool f = c == '-';T x = f ? 0 : (c ^ '0');for (c = getchar(); c >= '0' && c <= '9'; c = getchar()) {x = x * 10 + (c ^ '0');}a = f ? -x : x;
}
template <typename T, typename ...Argv>
inline void read(T &a, Argv &...argv) {
    read(a), read(argv...);
}

int n, m;
bool a[MAXn + 10][MAXm + 10];
int guass() {
    int row = 1, mxchoser = 0;
    for (int col = 1; col <= m && row <= n; ++col) {
        int choser = -1;
        for (int i = row; i <= n; ++i) {
            if (a[i][col]) {
                choser = i;
                break;
            }
        }
        if (choser == -1) continue;
        mxchoser = max(mxchoser, choser);
        if (choser != row) swap(a[row], a[choser]);
        for (int i = 1; i <= n; ++i) {
            if (i == row) continue;
            if (a[i][col]) {
                for (int j = col; j <= m + 1; ++j) {
                    a[i][j] ^= a[row][j];
                }
            }
        }
        ++row;
    }
    bool noans = 0, moreans = 0;
    if (row <= m) {
        for (int i = row; i <= n; ++i) {
            if (a[i][m + 1]) {
                noans = 1;
                break;
            }
        }
        if (noans == 0) moreans = 1;
    }
    if (noans) return 0;
    else if (moreans) return -1;
    else return mxchoser;
}

char str[MAXm + 10];
signed main() {
    read(m, n);
    for (int i = 1; i <= n; ++i) {
        scanf("%s", str + 1);
        for (int j = 1; j <= m; ++j) {
            a[i][j] = str[j] - '0';
        }
        scanf("%d", &a[i][m + 1]);
    }
    int res = guass();
    if (res == 0) {
        puts("Error1");
        exit(1);
    } else if (res == -1) {
        puts("Cannot Determine");
    } else {
        printf("%d\n", res);
        for (int i = 1; i <= m; ++i) {
            if (a[i][m + 1]) puts("?y7M#");
            else puts("Earth");
        }
    }
    return 0;
}