{"raw_statement":[{"iden":"problem statement","content":"In a factory, there are $N$ robots placed on a number line. Robot $i$ is placed at coordinate $X_i$ and can extend its arms of length $L_i$ in both directions, positive and negative.\nWe want to remove zero or more robots so that the movable ranges of arms of no two remaining robots intersect. Here, for each $i$ ($1 \\leq i \\leq N$), the movable range of arms of Robot $i$ is the part of the number line between the coordinates $X_i - L_i$ and $X_i + L_i$, excluding the endpoints.\nFind the maximum number of robots that we can keep."},{"iden":"constraints","content":"*   $1 \\leq N \\leq 100,000$\n*   $0 \\leq X_i \\leq 10^9$ ($1 \\leq i \\leq N$)\n*   $1 \\leq L_i \\leq 10^9$ ($1 \\leq i \\leq N$)\n*   If $i \\neq j$, $X_i \\neq X_j$.\n*   All values in input are integers."},{"iden":"input","content":"Input is given from Standard Input in the following format:\n\n$N$\n$X_1$ $L_1$\n$X_2$ $L_2$\n$\\vdots$\n$X_N$ $L_N$"},{"iden":"sample input 1","content":"4\n2 4\n4 3\n9 3\n100 5"},{"iden":"sample output 1","content":"3\n\nBy removing Robot $2$, we can keep the other three robots."},{"iden":"sample input 2","content":"2\n8 20\n1 10"},{"iden":"sample output 2","content":"1"},{"iden":"sample input 3","content":"5\n10 1\n2 1\n4 1\n6 1\n8 1"},{"iden":"sample output 3","content":"5"}],"translated_statement":null,"sample_group":[],"show_order":["default"],"formal_statement":null,"simple_statement":null,"has_page_source":true}