用C语言编写一个简单的加减乘除计算器，要求如图

#include #include int Calculate(char* input, float *ret){ int returnRet = 0; float num1, num2, symbol; int len = strlen(input); char* num1Str = (char*)malloc(sizeof(char) * len); char* num2Str = (char*)malloc(sizeof(char) * len); memset(num1Str, 0, len);