/* A C-program for MT19937: Real number version  (1998/4/6)    *//*   genrand() generates one pseudorandom real number (double) *//* which is uniformly distributed on [0,1]-interval, for each  *//* call. sgenrand(seed) set initial values to the working area *//* of 624 words. Before genrand(), sgenrand(seed) must be      *//* called once. (seed is any 32-bit integer except for 0).     *//* Integer generator is obtained by modifying two lines.       *//*   Coded by Takuji Nishimura, considering the suggestions by *//* Topher Cooper and Marc Rieffel in July-Aug. 1997.           *//* This library is free software; you can redistribute it and/or   *//* modify it under the terms of the GNU Library General Public     *//* License as published by the Free Software Foundation; either    *//* version 2 of the License, or (at your option) any later         *//* version.                                                        *//* This library is distributed in the hope that it will be useful, *//* but WITHOUT ANY WARRANTY; without even the implied warranty of  *//* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.            *//* See the GNU Library General Public License for more details.    *//* You should have received a copy of the GNU Library General      *//* Public License along with this library; if not, write to the    *//* Free Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA   */ /* 02111-1307  USA                                                 *//* Copyright (C) 1997 Makoto Matsumoto and Takuji Nishimura.       *//* When you use this, send an email to: matumoto@math.keio.ac.jp   *//* with an appropriate reference to your work.                     *//* REFERENCE                                                       *//* M. Matsumoto and T. Nishimura,                                  *//* "Mersenne Twister: A 623-Dimensionally Equidistributed Uniform  *//* Pseudo-Random Number Generator",                                *//* ACM Transactions on Modeling and Computer Simulation,           *//* Vol. 8, No. 1, January 1998, pp 3--30.                          */#include<stdio.h>/* Period parameters */  #define N 624#define M 397#define MATRIX_A 0x9908b0df   /* constant vector a */#define UPPER_MASK 0x80000000 /* most significant w-r bits */#define LOWER_MASK 0x7fffffff /* least significant r bits *//* Tempering parameters */   #define TEMPERING_MASK_B 0x9d2c5680#define TEMPERING_MASK_C 0xefc60000#define TEMPERING_SHIFT_U(y)  (y >> 11)#define TEMPERING_SHIFT_S(y)  (y << 7)#define TEMPERING_SHIFT_T(y)  (y << 15)#define TEMPERING_SHIFT_L(y)  (y >> 18)static unsigned long mt[N]; /* the array for the state vector  */static int mti=N+1; /* mti==N+1 means mt[N] is not initialized *//* initializing the array with a NONZERO seed */voidsgenrand(seed)    unsigned long seed;	{    /* setting initial seeds to mt[N] using         */    /* the generator Line 25 of Table 1 in          */    /* [KNUTH 1981, The Art of Computer Programming */    /*    Vol. 2 (2nd Ed.), pp102]                  */    mt[0]= seed & 0xffffffff;    for (mti=1; mti<N; mti++)        mt[mti] = (69069 * mt[mti-1]) & 0xffffffff;}double /* generating reals *//* unsigned long */ /* for integer generation */genrand(){    unsigned long y;    static unsigned long mag01[2]={0x0, MATRIX_A};    /* mag01[x] = x * MATRIX_A  for x=0,1 */    if (mti >= N) { /* generate N words at one time */        int kk;        if (mti == N+1)   /* if sgenrand() has not been called, */            sgenrand(4357); /* a default initial seed is used   */        for (kk=0;kk<N-M;kk++) {            y = (mt[kk]&UPPER_MASK)|(mt[kk+1]&LOWER_MASK);            mt[kk] = mt[kk+M] ^ (y >> 1) ^ mag01[y & 0x1];        }        for (;kk<N-1;kk++) {            y = (mt[kk]&UPPER_MASK)|(mt[kk+1]&LOWER_MASK);            mt[kk] = mt[kk+(M-N)] ^ (y >> 1) ^ mag01[y & 0x1];        }        y = (mt[N-1]&UPPER_MASK)|(mt[0]&LOWER_MASK);        mt[N-1] = mt[M-1] ^ (y >> 1) ^ mag01[y & 0x1];        mti = 0;    }      y = mt[mti++];    y ^= TEMPERING_SHIFT_U(y);    y ^= TEMPERING_SHIFT_S(y) & TEMPERING_MASK_B;    y ^= TEMPERING_SHIFT_T(y) & TEMPERING_MASK_C;    y ^= TEMPERING_SHIFT_L(y);    return ( (double)y * 2.3283064370807974e-10 ); /* reals */    /* return y; */ /* for integer generation */}/* this main() outputs first 1000 generated numbers  */main(){     int j;    sgenrand(4357); /* any nonzero integer can be used as a seed */    for (j=0; j<1000; j++) {        printf("%10.8f ", genrand());        if (j%8==7) printf("\n");    }    printf("\n");}