Cannot get value when working with struct in c

December 12, 2021

I am writing a program which prompt user to enter information of cities (in the program I test with 2 cities: city a, b) then print out these value. Each city has 4 value: name, income, population and literarte_rate. The problem is when I enter information literrate_rate, it automatically print out 0.000000 and save it to variable. I am still able to enter value to it and the next infomation.

Input

city name: qwerty 123 !@#
income: 789
population: 123456
literation: 0.000000685
city name: asdfgh 456 $%^
income: 456
population: 999999
literation: 0.00000065684

Output

city name: qwerty 123 !@#
income: 789
population: 123456
literation: 0.00
city name: asdfgh 456 $%^
income: 456
population: 999999
literation: 0.00

This is my code

#include <stdio.h>
#include <string.h>

typedef struct City
{
    char name[51];
    double income;
    unsigned int population;
    double literate_rate;
}city;

void input(city *tmp);
void output(city tmp);

int main(){
    city a, b;
    input(&a);
    input(&b);
    
    output(a);
    output(b);

    return 0;
}

void input(city *tmp){

    printf("city name: ");
    fgets(tmp->name, 50, stdin);
    tmp->name[strlen(tmp->name)-1]='\0';
    
    printf("income: ");
    scanf("%lf", &tmp->income);
    while(getchar()!='\n');
    
    printf("population: ");
    scanf("%d", &tmp->population);
    while(getchar()!='\n');

    printf("literation: ");
    printf("%lf", &tmp->literate_rate);
    while(getchar()!='\n');

}

void output(city tmp){
    printf("\ncity name: %s", tmp.name);
    printf("\nincome: %.2f", tmp.income);
    printf("\npopulation: %d", tmp.population);
    printf("\nliteration: %.2f", tmp.literate_rate);
}

I have tried to use while(getchar()!='\n'); after each scanf with number but it does not solve the problem.

So how to fix it and make more efficient?

Thanks in advance.