I was recently asked to compare the functionality of atoi() and std::stringstream.
Here’s the code:
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#include <stdio.h> #include <stdlib.h> #include <sstream> void strToInt(const char* str) { { // Set to garbage value. int val = 479894; std::stringstream stream; stream << str; stream >> std::dec >> val; printf("stream: '%s' -> %d\n", str, val); } { const int val = atoi(str); printf("atoi: '%s' -> %d\n", str, val); } printf("\n"); } int main() { strToInt(""); strToInt("0"); strToInt("a"); strToInt("1"); strToInt("44a"); strToInt("a44"); return 0; } |
And here’s the output:
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stream: '' -> 479894 atoi: '' -> 0 stream: '0' -> 0 atoi: '0' -> 0 stream: 'a' -> 0 atoi: 'a' -> 0 stream: '1' -> 1 atoi: '1' -> 1 stream: '44a' -> 44 atoi: '44a' -> 44 stream: 'a44' -> 0 atoi: 'a44' -> 0 |
So it looks like the functionality of both is actually very similar (though note std::stringstream has many ways to modify its behaviour); unfortunately it seems the stream doesn’t set the result to zero when given an empty string.