DouKaku?

#include <stdio.h>
#include <stdlib.h>

void tr_sub(char* c,char*src,char*dest){
    char from,to;

    while(*src){
        if(*(src+1)=='-'&&*(src+2)!='\0'){
            from=*src;
            to=*dest;
            do{
                if(*c==from){
                    *c=to;
                    return;
                }

                if(*src<*(src+2)) from++;
                else from--;
                if(*dest<*(dest+2)) to++;
                else to--;
            }while(from<=*(src+2));
            src+=3;
            dest+=3;
        }else{
                if(*c==*src){
                    *c=*dest;
                    return;
                }
            src++;
            dest++;
        }
    }
}

int tr(char *str, char* src, char* dest){
    char *p;
    int len_src;
    int len_dest;
    
    len_src=0;
    for(p=src;*p;p++){
        if(*(p+1)=='-'&&*(p+2)!='\0'){
            len_src+=abs(*(p+2)-*p)+1;
            p+=2;
        }else len_src++;
    }
    len_dest=0;
    for(p=dest;*p;p++){
        if(*(p+1)=='-'&&*(p+2)!='\0'){
            len_dest+=abs(*(p+2)-*p)+1;
            p+=2;
        }else len_dest++;
    }
    if(len_dest!=len_src) return -1;
    
    
    while(*str){
        tr_sub(str++,src,dest);
    }
    return 0;
}


int main(){
    char* text="typewriter";
    
    tr(text,"qwertyuiop","QWERTYUIOP");
    printf("%s\n",text);
    tr(text,"A-Z","a-z");
    printf("%s\n",text);
    tr(text,"p-r","r-p");
    printf("%s\n",text);
    tr(text,"p-r","rsp");
    printf("%s\n",text);
    
    return 0;
    
}