Interview Question : Trim multiple consecutive spaces from a string

Question

This is an interview question Looking for best optimal solution to trim multiple spaces from a string. This operation should be in-place operation.

input  =          


        

Answer 1

Here it is using only stdio:

#include 

int main(void){
    char str[] = "I    Like    StackOverflow a      lot";
    int i, j = 0, lastSpace = 0;
    for(i = 0;str[i]; i++){
        if(!lastSpace || str[i] != ' '){
            str[j] = str[i];
            j++;
        }
        lastSpace = (str[i] == ' ');
    }
    str[j] = 0;
    puts(str);
    return 0;
}