#define READY  0
#define RUNNING  1
#define WAITING  2
#define DONE  3

void rr(char *s1, char *s2, int quantum, int x1, int y1, int z1,                        int x2, int y2, int z2) {
   int i;
   int state1;
   int state2;
   int cpuLeft1;
   int cpuLeft2;
   int ioLeft1;
   int ioLeft2;
   int qleft;

   state1 = READY;
   state2 = READY;
   cpuLeft1 = x1;
   cpuLeft2 = x2;
   ioLeft1 = y1;
   ioLeft2 = y2;
   i = 0;
   qleft = quantum;
   while (1) {
      /* change state here if necessary and check if done */
      if ( (state1 == DONE) && (state2 == DONE) ) {
         break;
      }  
      if ((state1 == RUNNING) && (cpuLeft1== 0)) {
         if (ioLeft1 == 0) {
            state1 = DONE;
            s1[i] = 0;
         }
         else
            state1 = WAITING;
      }  
      else if ((state2 == RUNNING) && (cpuLeft2 == 0) ) {
         if (ioLeft2 == 0) {
            state2 = DONE;
            s2[i] = 0;
         }
         else
            state2 = WAITING;
      }  
      if ((state1 == RUNNING) && (qleft == 0) ) {
          state1 = READY;
          if (state2 == READY) {
             state2 = RUNNING;
             qleft = quantum;
          }
      }  
      if ((state2 == RUNNING) && (qleft == 0) ) {
          state2 = READY;
          if (state1 == READY) {
             state1 = RUNNING;
             qleft = quantum;
          }
      }  
      if ((state1 == WAITING) && (ioLeft1 == 0)) {
          state1 = READY;
          cpuLeft1 = z1;
      }  
      if ((state2 == WAITING) && (ioLeft2 == 0)) {
          state2 = READY;
          cpuLeft2 = z2;
      }  
      if ( (state1 == READY) && (state2 == READY)) {
            state1 = RUNNING;
            qleft = quantum;
      }  
      else if ( (state1 == READY) && (state2 != RUNNING)) {
         state1 = RUNNING;
         qleft = quantum;
      }  
      else if ( (state2 == READY) && (state1 != RUNNING)) {
         state2 = RUNNING;
         qleft = quantum;
      }  
      /* put somthing in based on the state */
      if (state1 == RUNNING) {
         s1[i] = 'R';
         cpuLeft1--;
         qleft--;
      }  
      if (state1 == WAITING) {
         s1[i] = 'w';
         ioLeft1--;
      }  
      if (state1 == READY) {
         s1[i] = 'r';
      }  
      if (state2 == RUNNING) {
         s2[i] = 'R';
         cpuLeft2--;
         qleft--;
      }  
      if (state2 == WAITING) {
         s2[i] = 'w';
         ioLeft2--;
      }  
      if (state2 == READY) {
         s2[i] = 'r';
      }  
      i++;
   }
}

void fcfs(char *s1, char *s2, int x1, int y1, int z1,
                        int x2, int y2, int z2) {
  rr(s1,s2,x1+z1+x2+z2,x1,y1,z1,x2,y2,z2);
}