測資生成器

#include <iostream>
using namespace std;
int main(){
    freopen("3.in","w",stdout);
    for ( int i = 0 ; i < 100 ; i++  ){

        int digit = rand() % 900 + 100;

        printf("%d",rand()%9 + 1);

        for ( int i = 1 ; i < digit ; i++ )
            printf("%d",rand()%10);


        printf("\n");

    }




    return 0;    
}

答案

#include <iostream>
#include <math.h>
#include <stdio.h>
#include <string.h>
using namespace std;
char input[1005];
int main(){
    //freopen("3.out","w",stdout);
    //freopen("3.in","r",stdin);
    while ( scanf("%s",input) == 1 ){
        int lsum = 0, rsum = 0;
        int len = strlen( input );
        for ( int i = 0 ; i < len ; i+=2 )    
            lsum += input[i] - '0';
        for ( int j = 1 ; j < len ; j+=2 )
            rsum += input[j] - '0';
        printf("%d\n",abs( lsum-rsum ));
    }

    return 0;    
}