矩阵模板

class Matrix { int[][] element; int r, c; public static Matrix getUnitMatrix(int r) { Matrix ret = new Matrix(r, r); for (int i = 0; i < r; ++i) { for (int j = 0; j < r; ++j) { ret.element[i][j] = (i == j ? 1 : 0); } } return ret; } public Matrix(int r, int c) { this.r = r; this.c = c; this.element = new int[this.r][this.c]; }; public Matrix(int[][] tmp, int r, int c) { this.r = r; this.c = c; this.element = new int[this.r][this.c]; for (int i = 0; i < this.r; ++i) { for (int j = 0; j < this.c; ++j) { this.element[i][j] = tmp[i][j]; } } } public Matrix multiply(Matrix m) { Matrix ret = new Matrix(this.r, m.c); for (int i = 0; i < this.r; ++i) { for (int j = 0; j < m.c; ++j) { int sum = 0; for (int k = 0; k < this.c; ++k) sum += this.element[i][k] * m.element[k][j]; ret.element[i][j] = sum; } } return ret; } public Matrix multiply(Matrix m, int mod) { Matrix ret = new Matrix(this.r, m.c); for (int i = 0; i < this.r; ++i) { for (int j = 0; j < m.c; ++j) { int sum = 0; for (int k = 0; k < this.c; ++k) sum += this.element[i][k] * m.element[k][j] % mod; ret.element[i][j] = sum % mod; } } return ret; } public Matrix pow(int n, int mod) { Matrix ret = Matrix.getUnitMatrix(this.c); for(; n!=0; n>>=1) { if((n&1) ==1) ret = this.multiply(ret, mod); this.element = this.multiply(this,mod).element; } return ret; } public int Tr(int mod) { int ret =0; for(int i=0; i<this.r; ++i) { for(int j=0; j<this.c; ++j) { if(i==j) { ret += this.element[i][j]; if(ret>=mod) ret = ret%mod; } } } return ret; } @Override public String toString() { StringBuffer sb = new StringBuffer(); for (int i = 0; i < this.r; ++i) { sb.append(Arrays.toString(this.element[i]) + "/n"); } return sb.toString(); } }