UVA - 465 Overflow

Overflow

Write a program that reads an expression consisting of two non-negative integer and an operator. Determine if either integer or the result of the expression is too large to be represented as a ``normal'' signed integer (type integer if you are working
Pascal, type int if you are working in C).

Input

An unspecified number of lines. Each line will contain an integer, one of the two operators + or *, and another integer.

Output

For each line of input, print the input followed by 0-3 lines containing as many of these three messages as are appropriate: ``first number too big'', ``second number too big'', ``result too big''.

Sample Input

300 + 3
9999999999999999999999 + 11

Sample Output

300 + 3
9999999999999999999999 + 11
first number too big
result too big

题意：

输入两个数和一个运算符

判断前面输入的两个数，和结果。是否超过int型的最大值

如果第一个数超过输出 first number too big

第二个超过输出second number too big

结果超过输出result too big

解析：

直接用字符串输入，然后用atof函数转化为double型就可以解决了。

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

const int MAX = 2147483647;
const int N = 1000;
int main() {
	char str1
, str2
, op; 
	while (scanf("%s %c %s", str1, &op, str2) != EOF) { 
		printf("%s %c %s\n", str1, op, str2);
		if (atof(str1) > MAX)
			printf("first number too big\n"); 
		if (atof(str2) > MAX)
			printf("second number too big\n"); 
		if ( (op == '+' && atof(str1) + atof(str2) > MAX) || (op == '*' && atof(str1) * atof(str2) > MAX))
			printf("result too big\n");
	}
	return 0;
}