Two's complement in C++ - invalid types 'int[int]' for array subscript -

i'm trying implement sort of two's complement algorithm in c++ , far think logic correct. however, following error when run invalid types 'int[int]' array subscript

#include <iostream> #include <stdio.h> using namespace std;  int main(){      int a[4] = {0, 2, 3, 5};     int b[4] = {9, 7, 8 ,4};      int sum = 0;     int transmit = 0;     int c{0};      (int k=3;k>0;k--){         sum = a[k]+b[k]+transmit;         c[k+1]=sum%10;         transmit=sum/10;     }      c[0] = transmit;     return 0; } 

i guess purpose plus operation of 2 int arrays? little explanation: have declare 5 units 'c' there may 1 additional carrier (you called transmit)

#include <iostream> #include <stdio.h> using namespace std;  int main(){      int a[4] = {0, 2, 3, 5};     int b[4] = {9, 7, 8 ,4};      int sum = 0;     int transmit = 0;     int c[5] = {0};      (int k=3;k>0;k--){         sum = a[k]+b[k]+transmit;         c[k+1]=sum%10;         transmit=sum/10;     }      c[0] = transmit;     return 0; } 

with format: array of decimal integers, hard converted binary directly. can still try give out solution:

// first convert unsigned int unsigned int result = 0; (int k = 0; k < 5; ++k) {     result *= 10;     result += c[k]; }  // convert binary char binary[32]; // 32bit should enough int len = 0; while (result > 0) {     binary[len++] = (result % 2) + '0';     result /= 2; }  // print binary (int k = len - 1; k >= 0; --k) {     printf("%c", binary[k]); } 

the full program:

#include <iostream> #include <stdio.h> using namespace std;  int main(){      int a[4] = {0, 2, 3, 5};     int b[4] = {9, 7, 8 ,4};      int sum = 0;     int transmit = 0;     int c[5] = {0};      (int k=3;k>0;k--){         sum = a[k]+b[k]+transmit;         c[k+1]=sum%10;         transmit=sum/10;     }      c[0] = transmit;      // first convert unsigned int     unsigned int result = 0;     (int k = 0; k < 5; ++k) {         result *= 10;         result += c[k];     }      // convert binary     char binary[32]; // 32bit should enough     int len = 0;     while (result > 0) {         binary[len++] = (result % 2) + '0';         result /= 2;     }      // print binary     (int k = len - 1; k >= 0; --k) {         printf("%c", binary[k]);     }      printf("\n");      return 0; }