/** 第三题code */ #include <iostream> #include <string.h> using namespace std; typedef long long lld; const lld MAX_LEN = 1001; const lld MOD = 1000000007; class Matrix { public:     Matrix(const Matrix &rhs) {         memcpy(v, rhs.v, sizeof(v));     }     Matrix() {         memset(v, 0, sizeof(v));     } public:     lld * operator[] (int index) {         return v[index];     }     lld * operator[] (int index) const {         return (lld*)v[index];     } public:     lld v[2][2]; }; Matrix operator *(const Matrix &lhs, const Matrix &rhs) {     Matrix r;     for (int i = 0; i < 2; ++i) {         for (int j = 0; j < 2; ++j) {             for (int k = 0; k < 2; ++k) {                 r[i][j] += lhs[i][k] * rhs[k][j];                 r[i][j] %= MOD;             }         }     }     return r; } Matrix QuickPow(const Matrix &m, const lld n) {     if (n == 1) {         return m;     }     else if (n % 2 == 0) {         const Matrix &tm = QuickPow(m, n >> 1);         return tm * tm;     }     else {         const Matrix &tm = QuickPow(m, n >> 1);         return tm * tm *m;     } } lld GetResult(const Matrix &m) {     return ((m[1][0] * 3 + m[1][1] * 2) % MOD + MOD) % MOD; } int main() {     Matrix m;     m[0][0] = 3, m[0][1] = -1;     m[1][0] = 1, m[1][1] = 0;     int ic;     cin >> ic;     lld n;     while (ic--) {         cin >> n;         if (n == 0) {             cout << 1 << endl;             continue;         }         cout << GetResult(QuickPow(m, n)) << endl;     } } /** * 第二题code */ #include <iostream> #include <fstream> #include <string.h> using namespace std; typedef long long lld; lld MOD = 1000000007; lld dp[1001][1001]; void init(); //fstream r("1.in"); //fstream w("1.out"); int main() {     init();     lld k;     cin >> k;     while (k--) {         lld m, n;         cin >> m >> n;         cout << dp[m][n] << endl;     } } void init() {     memset(dp, 0, sizeof(dp));     dp[0][0] = 1;     for (int r = 0; r <= 1000; ++r) {         for (int c = 0; c <= r; ++c) {             if (r > 0 && c > 0) {                 dp[r][c] = dp[r - 1][c - 1] + dp[r - 1][c];             }             else if (r > 0) {                 dp[r][c] = dp[r - 1][c];             }             dp[r][c] %= MOD;         }     } } /** 第一题code */ #include <iostream> using namespace std; int n; int m; int main() {     cin >> m;     while(m--) {         cin >> n;         if (n % 3) {             cout << "lucky" << endl;         }else {             cout << "don't be discouraged" << endl;         }     } } 不要谢我，我是雷锋