1 #include <stdio.h> 2 #include <math.h> 3 int main() 4 { 5 double data1, data2; 6 char op; 7 while (3 == scanf("%lf%c%lf", &data1, &op, &data2) ) 8 { 9 double result; 10 printf("%lf%c%lf=", data1,data2); 11 switch (op) 12 { 13 case '+': 14 result = data1 + data2; 15 break; 16 case '-': 17 result = data1 - data2; 18 break; 19 case '*': 20 result = data1 * data2; 21 break; 22 case '/': 23 result = data1 / data2; 24 break; 25 default:; 26 } 27 printf("%lf ", result); 28 } 29 30 return 0; 31 }
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说明：上面的代码在计算特定运算时会出现舍入错误，原因待定，修改代码如下解决。
1 #include <stdio.h> 2 int main() 3 { 4 float data1, data2; 5 char op; 6 while (3 == scanf("%f%c%f", &data1, &op, &data2) ) 7 { 8 float result; 9 printf("%f%c%f=", data1, op, data2); 10 11 switch (op) 12 { 13 case '+': 14 result = data1 + data2; 15 break; 16 case '-': 17 result = data1 - data2; 18 break; 19 case '*': 20 result = data1 * data2; 21 break; 22 case '/': 23 result = data1 / data2; 24 break; 25 default:; 26 } 27 printf("%f ", result); 28 } 29 30 return 0; 31 }