#include <stdio.h>
int main() {
    int a, b, c, d;
    char op;
    
    if(scanf("%d %d", &a, &b) != 2) return 0;
    if(scanf("%d %d", &c, &d) != 2)return 0;
    scanf(" %c", &op);
    
    int real = 0, imag = 0;
    
    switch (op) {
        case '+':
        real = a + c;
        imag = b + d;
        break;
        
        case '-':
        real = a - c;
        imag = b - d;
        break;
        
        case '*':
        real = a * c - b * d;
        imag = a * d + b * c;
        break;
        case '/': {
            int denom = c * c + d * d;
            if (denom == 0) {
                printf("Invalid input");
                return 0;
            }
            real = (a * c + b * d) / denom;
            imag = (b * c - a * d) / denom;
            break;
    }
    if(imag >= 0)
        printf("%d + %di", real, imag);
    else
        printf("%d - %di", real, -imag);
    
    return 0;
}