小编yos*_*105的帖子

 #include <iostream> // cin, cout
using namespace std;
int main(void)
{
char c[80];
int i, sum=0;
cin.getline(c,80);
for(i=0; c[i]; i++) // c[i] != '\0'
if('0'<=c[i] && c[i]<='9') sum += c[i]-'0';
cout<< "Sum of digits = " << sum << endl;
getchar();
getchar();
return 0;
}

我理解一切都接受了总和+ = c [i] - '0'; 我删除了"-'0",它没有给我正确的答案.为什么是这样？

package PJ2;
import java.util.*;

public class SimpleLispExpressionEvaluator
{
    // Current input Lisp expression
    private String inputExpr;

    // Main expression stack & current operation stack, see algorithm in evaluate()
    private Stack<Object> exprStack;
    private Stack<Double> currentOpStack;


    // default constructor
    // set inputExpr to "" 
    // create stack objects
    public SimpleLispExpressionEvaluator()
    {
    // add statements
        inputExpr = "";
        exprStack = new Stack<Object>();
        currentOpStack = new Stack<Double>();
    }

    // default constructor
    // set inputExpr to inputExpression 
    // create stack objects
    public SimpleLispExpressionEvaluator(String inputExpression) 
    { …