1165: decimal part of real number (pointer)

1165: The fractional part of a real number （ Pointer theme ）

Title Description
Read in a real number , Output the decimal part of the real number , If the decimal part is redundant, the end 0, Please remove . Such as the input 111111.12345678912345678900
The output 0.123456789123456789. If you remove the end 0 After that, the decimal part is 0, The output “No decimal part”. Note that the number of digits of the real number does not exceed 100 position .
Please define and use the following functions .
char *decimal(char *p)
{
The string p The decimal part from the decimal point of the real number represented by is stored in a string , And the function returns , if p by “123.456”, The returned string is “.456”. If the decimal part is 0, Return null pointer NULL.
}
Input
Enter a real number . No more than 100 position .
Output
Output decimal part , Output takes up one line .
The sample input Copy
111111.12345678900012345678900
Sample output Copy
0.123456789000123456789
source / classification

#include<stdio.h>
#include<string.h>
#define N 102

char *decimal(char *p){
    
    char *q;
    int k=0;
    q=(char *)malloc(sizeof(char)*N);
    
    for(int i=0;p[i]!='\0';i++){
    
        if(p[i]=='.'){
    
            for(int j=i;p[j]!='\0';j++){
    
                q[k++]=p[j];
            }
            q[k]='\0';//'\0' Control character for the end of output 
            break;
        }
    }
    k--;
    // Get some extra 0
    while(q[k]=='0'){
    
        q[k]='\0';
        k--;
    }
    if(q[k]=='.') return NULL;
    return q;
}
int main(){
    
    char *p;
    p=(char *)malloc(sizeof(char)*N);
    gets(p);

    if(decimal(p)==NULL) printf("No decimal part\n");
    else printf("0%s\n",decimal(p));
    return 0;
}