#include<stdio.h>
#include<stdlib.h>	
#include<string.h>	
	int main(void){
	void run_func(char *map[], char *fnt  , char *km , float *x ,  float *y , int line , int row , int lift    );
				char *long_met[3][8] = {{"mile","0.621371"  ,  "yard","1093.61" , "fut","3280.84" , "duim","39370.1" } ,
							{ "mile" ,"1.60934" , "yard","0.0009144" ,  "fut","0.0003048" ,  "duim","0.0000254"},
 			   				{"kilometer","1"  , "meter","1000"  ,   "stmeter","100000" ,   "mmeter","1000000" } }; 
				char *amount[3][4] = { { "gallon" , "0.264172" ,       "quarta" , "1.05669"     } , 
						{"gallon" , " 3.78541"  ,     "quarta" , "0.946353"   },
						{"litr" , "1"  , "mililitr" , "1000"   }};
				char *mass[3][8] = {   {"eng.tonna","0.984207"  ,  "amer.tonna","1.10231" , "stone","157.473" , "funt","2204.62" } ,
   						{ "eng.tonna" , "1.01605" , "amer.tonna", "0.907185" ,  "stone","0.00635029" ,  "funt","0.000453592"},
						{"tonna","1" ,         "kilogram" , "1000"  , "miligram","100000"   , "microgram","1000000"  }}; 
				char **cp;
				char *buf_data;
				char *fnt_sys;
				char *mtr_sys;
				char *word[100];
	while(1){
	int bg  = 0,convert_ch = 3,y = 0, d = 0, numb = 0;
  	float mn =0  , xm = 0 ;
	printf("%s", "enter data for converter: ");
		fgets( (char *) word, 99 ,stdin);
		buf_data = strtok((char *) word, " ");
		if( ! strcmp(buf_data, "funt.sys"   )     ){
		convert_ch = 0;	
		}
		else	if( ! strcmp(buf_data, "metric.sys"    )     ){
			convert_ch = 1;	
		}
		for( bg = 0 ;  buf_data != NULL;  buf_data = strtok(NULL, " ")  , bg++ ) {
			switch(bg){
				case 1:
					if( !strcmp("long_met" , buf_data  )  ){
			  			 y	=   sizeof(*long_met) / sizeof(long_met[0][0]); 
	          	      	                 d	=   sizeof(long_met) /   sizeof(long_met[0][0]); 
			  		        cp  = &long_met[convert_ch][0]  ;
					}
			   		else if(!strcmp("amount" , buf_data  ) ){
			  			 y	= sizeof(*amount) /  sizeof(amount [0][0]); 
		            	                 d	= sizeof(amount) /  sizeof(amount[0][0]); 
				    	        cp = &amount[convert_ch][0] ;
					}
				 	else if(!strcmp("mass" , buf_data  ) ){
				  		 y	= sizeof(*mass ) /  sizeof(mass[0][0]); 
		         		         d	= sizeof(mass ) /  sizeof(mass[0][0]); 
				 		 cp = &mass[convert_ch][0] ; 
					}
					break;
				case 2:
				fnt_sys = buf_data;
					break;
				case 3:
				mtr_sys = buf_data;
					break;
				case 4:
				numb =   atoi(buf_data);
					break;
			}
		}
		if( !y || !d || !cp || convert_ch == 3 || !numb ){
	
			puts("error");
		}
		else{
			run_func( cp,   fnt_sys ,  mtr_sys , &mn ,  &xm , y  , d , convert_ch );
			if( !mn || !xm  ){
		puts("error");
				} else{
			printf("%f\n" , !convert_ch  ?    (mn  /  xm ) * numb :  (  mn  *  xm   ) * numb         );	
			}
		}
	}
	return 0;
	}
	void run_func(char *map[], char *fnt  , char *km , float *x ,  float *y , int line , int row  , int lift    ){
		int m ;
	if(  ( lift )   ){
			row    -= line;	
		}
	for(  m = 0 ; m <= line   ; m++){
		if(!strcmp(fnt,map[m])){
			*x = atof(map[m  + 1] )  ;
			break;
			}
		}
	for( m =   (row  - line) ; m <=  row - 1  ; m++){
		if( !strcmp( km   ,  map[m] ) ){
			*y = atof(map[m  + 1 ] );
			break;
				}
			}
		}