プログラマ専用SNS ミクプラ

コード:

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#define N 256
int sum(int b);
int main (void) {
FILE *fp;
char filename[100];
int b;
sum(b);
sprintf(filename,"%d.txt",b);
char readline[N] = {'\0'};
if((fp=fopen(filename, "r")) == NULL) {
printf("not open\n");
exit(1);
}
while ( fgets(readline, N,fp) !=NULL) {
printf("%s",readline);
}
fclose(fp);
return (0);
}

int sum (int b) {
char i[100];
printf("県を入力してください\n");
scanf("%s",i);
if(strcmp(i,"siga")==0){
b=1;
}
else if(strcmp(i,"nara")==0){
b=2;
}
else if(strcmp(i,"wakayama")==0){
b=3;
}
else if(strcmp(i,"osaka")==0){
b=4;
}
else if(strcmp(i,"kyoto")==0){
b=5;
}
else if(strcmp(i,"hiyogo")==0){
b=6;
}
else{
printf("gomen\n");
}
return(b);
}